It’s updated whenever your package manager puts up the new version. If you’re using something like Ubuntu or Mint, then you’re using apt as your package manager, which takes a while to update stuff because they like to test it for a while first.
Not everyone feels like having a mascot fits with their branding
I didn’t get to spend too too much time doing pro audio on linux because as soon as I realized Wwise will not work, I didn’t spend much more time in Reaper after that. But it was good, especially with an audio interface (if you’re buying an audio interface, check to see how well it works with linux. Apparently some may have issues)
By the way, the whole point of Debian is that it has older software, and in exchange you’re almost guaranteed to have a system that doesn’t break. But for some professional software you’ll want the newest version. I recommend using Flatpak for that stuff instead of Apt (like for Reaper)
When installing Debian, when it asks “Allow login as root?” be sure to select “no”. This one step is why some people don’t recommend Debian, saying it complicates the install process. But if you get that right, then you’re all good. Or I think sometimes it will instead ask you to create and type in a root password, in which case you should leave it blank and click next. You only want to make a password for your user, not for the root.
First off, I want to make it clear that the distro doesn’t really matter. Different distros are just what it comes pre-packed with by default.
TLDR:
For something easy to use: Linux Mint
For something that has pre-installed audio software (but maybe not the ones you want): Ubuntu Studio
If you want to build your system from scratch: Debian (or Arch if you want the latest and greatest software, and don’t mind the occasional update breaking your system around once a year or so, and needing to spend an hour fixing it)
Regardless of which distro you get, use JACK or PipeWire for your sound server. PulseAudio (on its own) has too much latency.
More details:
I first tried Ubuntu Studio. It comes with a lot of software related to audio production. But I found it to be insanely slow, and it didn’t even come with Reaper anyway.
I tried OpenSUSE because I liked that it had the option to manually deselect the software you don’t want (and I was too much of a beginner to know how to pick my packages from the ground-up). It worked well.
Eventually I moved to Debian. I didn’t want any of the extra fluff and found it was pretty easy to choose everything myself. One thing that’s important is that you don’t want to use PulseAudio. Either use JACK (which I think needs to be used in conjunction with PulseAudio actually) or use PipeWire, which is what I use.
For any Windows software, use Bottles to emulate them on Linux. I actually ended up needing to go back to windows because of one audio software: Wwise. There was no way of running it in Linux. A VM probably would’ve worked, but that would’ve been a massive hassle for how I’d need to use it.
Free Linux VSTs: https://vital.audio/ https://lsp-plug.in/ https://github.com/TukanStudios/TUKAN_STUDIOS_PLUGINS
Paid Linux VSTs: https://www.acmt.co.uk/products/index.html https://librewave.com/ https://www.audiodamage.com/collections
Regardless of the distro, you can install as many desktops you want. It doesn’t have to be during the OS’s installation screen.
You’ll want to decide on a desktop environment or window manager (or compositor). That’ll be the biggest determining factor of what things will look like. From there, you’ll want to either read the manual or arch wiki on how to customize the different aspects of it.
If you decide you want a tiling window manager, Hyprland is nice since you mentioned you wanted animations. But it’s only recommended on rolling release distros at the moment. It also might not work well with Nvidia.
What kind of “app behaviour” customizations are you wanting to do? That sounds like it would be app-specific. My main form of app customization is to find ways to change the colour scheme (to fit everything else), and also to change the keybindings (I like using vim-like key bindings whenever reasonable)
proprietary software that I don’t trust, or programs that aren’t on zypper