What OS have you used in order from

old macOS from/on an old Power Mac desktop
Windows 95
Windows 98
Windows XP
Windows Vista
Windows 7
Windows 8
Windows 8.1
Windows 10
Manjaro

I've used most popular/common distros like Ubuntu and such but I prefer Manjaro

Indians taking planking too far.

Windows 98
Windows XP
Windows 7 and Linux Mint
Windows 8.1 and Linux Mint
Windows 10 for an hour
Linux Mint
*buntu
Arch
Korora
Fedora for an hour
Linux Lite
Chalet OS

Also I use windows XP in a VM for Office and Photoshop compatibility

Amiga Workbench
Windows
Linux

oh forgot
mac os (about 7 years)
nextstep (5 years)
slackware (1-2 years)
debian (3 years)
slackware (a few months)
os x (15 years)

CP/M on an old Kaypro II - 2 yr
Mac Plus (System 6) - 3 yrs
Mac Performa 450 (System 7.0) - 4 yrs
Windows 95 - 4 yrs
Windows 98 - 2 yrs
Windows Me - 1 yr
Windows XP - 7 years
Windows 7 - 3 years
Windows 8(.1) - 2 years
Windows 10 - 1 year

windows 98
windows xp
xubuntu
debian squeeze
windows 8
windows 10
arch linux

probably will never go back to another windows system.

Windows ME - 3 years or so
Windows Vista - 2 years or so
Windows XP - 2 years
Windows 7 - 1 year
Arch - 1 year
Ubuntu - 2 years
OS X - 3 years

Nobody else went backwards to XP?

I didn't try running Vista on shit hardware so it was an actual upgrade for me.

I'm surprised no Windows NT or OS/2.

For me it was actually because I used a netbook as my primary computer for a while. I still had Vista on my desktop.

I'll be honest my memory is pretty foggy. But from 1st grade onwards my primary operating systems were:
System 7 "Mac Os 7"
Windows 95
Windows 98
Windows XP
Windows Vista
Ubuntu
Windows 7
Linux Mint
Windows 8 (reinstalled 7)
Mac OS 10
Windows 10 (reinstalled 7)

DOS
Win1.0
Win3.1/WinNT3.1
Win98
Win2000/RedHat
WinXPSP1/OS9
Win7
Win10/OSX/Xubuntu/Arch

NT 3.1 for a while
OS/2 like a couple of months on one computer. Don even remember why I did that.

Windows 95 -- 1997 until 2001
Mac OS X -- 2001 until now
Linux (all flavors) -- 2000 until now
IRIX -- 2014 until now

MS Color Basic 1.0
TRSDOS 1.3 w/ DeskMate
MS-DOS (several versions, from 3.3 up to 6.22)
Windows 3.1
Windows 95 & 95 OSR2
Windows NT 4.0
Windows 98 & 98 SE
Red Hat 5.2
Windows XP Home & Pro
Puppy Wary 5.5
Puppy Slacko 6.3
Lubuntu 15.10

Win 95
Win XP
Ubuntu
Win 7
Debian
Win 7/Mint

Macintosh System 6 - First couple years with a computer
Windows 95 - 3 years[?]
Windows 98 - 3 years[?]
Mac OS 9 - 5 years
OS X - 10+ years
Debian / WindowMaker Live - A few months on my ThinkPad.

10.4 is the best version of OS X, I run it on my PPC machines and it still feels modern.

Yeah, I love Tiger

Windows 95 4 years
Windows XP 5 years
Windows 7 3 years
Mint Linux 1 year
Antergos Linux 2 years
Fedora Linux since last week

20 years old. Probably gonna stick with Fedora.

Win XP 3y
Win7 1y
Debian 4y
Arch 5y-

Windows 3.1 - 1 year
Windows 95 - 5 years
Windows 2000 - 7 years
Windows xp - 2 years
Windows 7 - 9 or so months
Ubuntu - 1 year
Debian - 3 months
Lubuntu - 6 months
Fedora - 2 weeks
Manjaro - 3 or 4 days
Arch - 4 years

Maybe gentoo or LFS one day in the future but I'm enjoying arch too much right now

I don't remember exact time frames but I do remember the order

BASIC
Win 3.1
Win 95
Win 98
Mac (briefly - hated proprietary hardware)
Redhat Linux (second IRC machine)
Win ME and Mandrake (second IRC machine)
Win ME and Slackware 4.0/7.0 (second IRC machine)
Win XP and Redhat 7.3
Win XP and Redhat 8
Win XP and Redhat 9
Win Vista
Win 7
Ubuntu exclusively for about a month
Debian exclusively for over a year

Most likely Debian going forward, it just werks

MacOS 7.1.2(?)
Windows 98
XP
Vista - 3 years
7 - 5 years
10 - three weeks

Windows 98 idk
XP -idk
w7 -idk

ubuntu
Arch
W8 - like a week or two
Debian.
W10.
Mac OSX El capitan.
Ofc i triple boot the last three on my desktop and use ubuntu on my laptop with Awsome Wm

MS DOS 5.0 - early 90's, dad's home office PC, games or any not work related software was banned so I wrote shitty text adventures for myself first in batch script, then in Quick Basic, finally in Turbo Pascal. I was around 12 then and I forever regret there was no one who knew better to tell me to learn C instead.
MS-DOS 6.22 - early to mid 90's, still have the 386 from back then and it's running strong, pic related.
Windows 3.1 then 3.11 - mid 90's for a year or two, start of dial-up internet and getting absolute shit from my parents over phone bills every month.
Windows 95 - 1996 to 2002, was the poorest of poorfags back then running the same shitty toaster all this time.
Windows 2000 - 2002 to 2007, would absolutely go back to it if it wasn't 100% obsolete now.
GANOO LOONIX - 2007 to 2009-ish, my motherboard and CPU got fried, had no money for new proper PC, had to buy a shitty Pentium 133 box to sustain me and I fell for the loonix performance meme, I even installed it from the source. I shit you the fuck not, I compiled Gentoo with X11 and everything on a fucking Pentium 133, it took like a fucking week, and that was centuries before you faggots came up with the "install gentoo" meme. I used it in terminal most of the time it taught me a fuckton about linux, talk about being thrown on a deep water.
Windows XP - 2009 to 2011, got a hand me down shitbox that was still miles better than the Pentium, I hated XP but couldn't be fucked getting anything else.
Windows 7 - 2011 until present, became a wagecuck in the meantime, saved a lot of money, finally built a top tier gayman PC which was my dream since I was 12, realised I now have no time for vidya due to being wagecuck, trying not to kill myself every night.

tl;dr, nice blog.

Managed to boot up my loonix too when I was cleaning up the closet, here it's plugged into the XP era shitbox. It booted fine but I couldn't remember my user or root password kek.

System 6
Mac OS 9
Mac OS X (through 10.5)
---discovered freedom
Ubuntu
Debian
GuixSD

Some others in there, but nothing worth mentioning.
Guix has changed the way I think about operating systems.
Nothing else touches it - All others will from here on out feel wrong and lacking and crippled.

DOS : 6 months or so
Win95-98 : 3 years
XP : 6 years
7 : 2 years
Ubuntu : 4 years
7 : 2 years for gaymes
Arch : 5 years

using linux toy for fun with additional feature it can be used at my job

Atari TOS - from age 0 to age 10
Windows 95/98/2000 - from age 10 to age 16
Windows xp - from age 16 to age 22
Mostly linux and some osx - From age 22 to 31

Windows 98
Windows XP
Windows 7
Windows 8.1
Manjaro

95 - probably like 6 years
XP - 11 or so years
CrunchBang - 2 years
10 - a few weeks.
arch and funtoo - about a year now.