For what it’s worth, the multi-user experience in my case has been pretty seamless. Here’s my setup if it helps anyone:

My roommate and I both have separate steam accounts (it sounds like you may be looking for a ‘child’ account or something like that, those may be a thing but I’m unfortunately completely unfamiliar with that, so ymmv if you use that).
We set up family sharing between us to access each other’s games, but did that I think entirely on a computer via that steam client. No pins or anything were necessary iirc, just a slightly convoluted sequence of logging in and out of steam on the same computer and clicking the needed ‘family sharing’ buttons.

Then I set up the deck with my account, logged out, and had my roommate log in. There’s an option somewhere to start the steam deck at the account select screen every time it turns on rather than automatically logging in to the last used account.

It sounds like most of the difficulty is coming from the family sharing setup. Like I said, I’m not knowledgeable on if steam has ‘child’ accounts that can be linked to other accounts, if so it’s possible that none of what my process was like applies.

Hopefully that’s at least somewhat helpful

I know iFixit sells screw extractor bits that apparently work well, though I haven’t tried them myself: https://www.ifixit.com/products/precision-screw-extractor-set Might be with checking out these or something similar

For me it was pretty gradual. In my university research a couple years ago I needed to work with the university’s supercomputer running RHEL, so I got some exposure there. At some point I put Mint on my laptop, keeping Windows on my desktop “in case I needed to do any real work”, then about a year ago I put linux* on my desktop as well. I do still have a Windows dual-boot just in case there’s some weird software I need to use, but I haven’t touched it more than once or twice since. I switched partially out of curiosity, but largely as part of an effort to de-google and de-microsoft my stuff so I’m more in control.

*distro-hopped a bit, but now am settled on EndeavourOS

I was surprised at how much you needed the terminal, but also how easy it was to use the terminal after a bit of practice. I prefer it to GUIs for a lot of things now (like git). Also, installing software from a package manager rather than going to a website and downloading it. I didn’t like that at first, but I love that concept so much more now, since I can just sudo apt upgrade and everything is up-to-date (no downloading the new version after an update).

I’m now to the point that when I do need to use a windows machine for some reason, it takes me a second to remember how things work. It’s kinda a weird feeling tbh haha