Re: Because ... it’ll just work : Nope
2011 13" Macbook Pro here. Actually thinking of upgrading to a 2015 15" MBP so I can install the latest OSX without witchcraft, but not because my old workhorse doesn't do what I need it to.
I set up some ancient IBM Thinkpads from 2006 to do remote work over VNC/Wireguard for a couple of guys during the pandemic.
I think my record was a Mac SE/30 that ran NetBSD and used as a test web and mail server for a really long time, decommissioned only a decade ago or so. If you have the time to trawl ebay for SIMMs, the SE/30 will take up to 128MB of the things. Definitely one of the best computers ever made.