I'm aware of Debian's reputation for not having the most up-to-date software in its repository but have just noticed that Thunderbird is on its current version. Which makes me ask:
When does Debian update a package? And how does it decide when to?
I'm particularly interested in when it will make available the upcoming major release of GIMP to 3.0.
You can always use APT Pinning to grab GIMP and its dependencies from testing without touching the rest of the system.
Or you can just run testing or sid as your base system. My gaming rig is based on testing but pulling Mesa and video derivers from experimental and sid and I haven’t had any issues with it. Been running it for about 2 years now this way.
what i mean by production is "not randomly breaking because it's feature freeze time and now i have to reinstall everything". i assure you it's not a high bar
sorry if i sound a little annoying about this, it's just that i've seen so many people recommending debian testing as if it's just a different flavor of debian for people who want a more up-to-date system and are willing to deal with a little instability, but it is not that. debian testing is made exclusively for testing debian. it is not made for daily driving. i've had so many issues with debian systems in my lab which i later found out were caused by someone "upgrading" the system to testing bc they heard debian testing is the daily driving version and debian stable is just for servers that need 99.9% uptime
honestly, you'd be better off using sid rather than testing, since it's rolling release
as for gimp, they can just use pinning to upgrade gimp exclusively. they can also use backports. no need to upgrade the whole system