Affected your user and not the system as a whole, yes.
If you want to be a hyper technical dick like the other person responded, the old way to refer to the term "userspace" is basically anything that doesn't affect the kernel, HOWEVER, it is now more commonly used to refer to specific local user settings, yes. The old reference was way before people starting writing things to be hyper-local to individual users, as things are arranged now.
It doesn't have anything to do with the distro. With that many files, you're torturing the hell out of your disks, and your machine's memory. Depending on how the code is written, it depends on if this is a filesystem scan of the folders that are then imported to a local db which is looked up to go back and find the found files, or a simple approach which is to just scan the directory every time you go to open something.
I'd really think about properly organizing your files. If that's not an option, you can dig into the settings or code and find the hard limits set (probably for a good reason) on the number of files being scanned or imported.
Don't they all make that claim?
What's the controversy?
There are lots of BIOS options that impact USB devices, and especially input devices. I'd start digging. If anything, I'd try plugging into the USB ports that are connected to the main bridge at the top of the board, and not any that are extended via passthrough cable. On some boards, those USB ports are set to emulate PS2 serial.
What in the world is that gold thing on the left?
Okay, but are they actually running?
Login and check that the processes actually started, and check logs to see if they had any failures.
Anything done locally that only affects your user is userspace. Doing configuration changes in userspace versus globally will reduce the likelihood of you breaking something. So making changes in ~/.local, for example, instead of /usr/local.
Did you check that your services are actually starting on boot?
Unless you've absolutely made the kernel or package manager unusable, there should be no need to reinstall an entire Linux OS. It's not like Windows where the registry changes over time, and the OS will become unstable or quirky. It sounds like you just need to be more diligent about doing things in userspace.
Y'all need to really stop recommending immutable distros to people who aren't even familiar or know what their regular setup will be. Like this poster who even said they are still going to have to work out Windows alternatives.