The "best" user experience you're referring to is getting surprises like your OpenSSH 9 suddenly stopping to work with your key agent [1] out of the blue because they decided to change the protocol (no big deal right?) without any hint of this whatsoever during normal usage, and you just casually upgraded your packages because, well, when did Linux package upgrades ever hurt anybody?
(Just the latest incredibly frustrating surprise your fellow "Windows person" literally had to spend hours on tracking down. And that I actually remember. Most definitely not the only one.)
Debian Stable tends to hand pick the latest LTS version of packages everywhere applicable, so it's actually a good base to standardize on. Packages might be a bit older but they are reliable, predictable, and kept secure by a constant roll of security updates.
In other words, if it doesn't work on the latest Stable, you're probably moving too fast for a good part of the industry. Lots of customer and production stacks are not in the "move fast, release early, release often, and link the crap to the very latest bleeding edge dependency" bandwagon.
The whole point of stable vs testing is that versions are fixed, reviewed security updates make it, it’s all tested and vetted.
On the other hand, testing and backports haven’t been tested as well and could have issues.
If we use stable and incorporate backports from testing, is it still stable?
If I knew about Arch earlier I would have switched, because it sounds like my kind of distro - but I have to much customizations and too much kids to have time for that right now.
I never quite get why people want they development environment be similar to production - you install IDE on production? Or you just code in vim/emacs/ed without any plugins (because production doesn't need it)?
It just so happens the software you mentioned, git, is in stable backports, so it is updated frequently. Regardless, I've been on Debian stable since 2007, and running "bleeding edge" stuff is trivial, depending on your desired workflow. (For example, I just install Debian testing packages in a schroot.) I used to bounce from distribution to distribution in the old days (Red Hat, Mandrake, Slackware, Gentoo, etc.) but once I found Debian Stable I could concentrate on getting work done.
For me it’s definitely been browsers and IDE’s, but I just install those to /opt.
Most of breakages of Linux was my own doing (e.g. by mistake overwritting MBR).
I use testing+unstable (I didn't know that backports exists, thanks) + self compile some software that doesn't exist in either or is too old. I also always compile kernel, prefer it to have less modules and configured towards performance on desktop.
So I might be two years out of date on ls, but it probably hasn't changed in the last 2 years anyway.
It’s really nice to have the rest of the distribution more or less set it and forget it.
Even just the git has many releases during Debian Stable/Ubuntu LTS, which enhance user experience, that holding back users is not the best idea. And in most cases security fixes land first in the newest versions and are backported, so it is most likely to have a fix in HEAD than in some random older release.