I don't know how old this document is, but I created my own PDS this weekend and it's not have to join their Discord server to do so.
I did some very rough estimates and found that the amount of aluminum entering the Earth's atmosphere each year is probably between 100 and 500 tons, which would be roughly comparable to the amount coming from these LEO comm sats like Starlink.
These are just super ballpark figures, but it's in the same order of magnitude. More research is definitely necessary.
Check out the Culture series by Iain M Banks
Check out Framework if you haven't already! https://frame.work/linux
They're designed to be upgraded and repaired over time so they're super modular. You can also save some money if you're not afraid to put it together yourself.