That’s all well and good, but there’s also a point of simply keeping up with the times, and having all your software up to date. My early 2011 15” mbp has seen a few logic board replacements due to a hardware design flaw. Regardless, it’s been running smoothly except for third party kernel extensions that wasn’t updated and stuff like that. So if it’s self-inflicted misadventures due to lack of understanding or wanting to keep things in check, and potentially scrapping a few plugins here and there, that no longer/for the time being aren’t stable/compatible, then that’s what you have to work with. And that can result in both a faster, and potentially even more reliable or effective setup, that supports the current market, and all the newest features and tools you’ll come across. Potentially lower your latency, give you a higher quality audiopath and more efficient use of your system (32bit vs 64bit etc.) That’s kinda the beauty of Apple. If things are supported, it’ll usually run just as smooth if not better, if you keep everything up to date ;)
I installed a 500gig samsung evo 850 and scrapped the old hdd, and this thing runs stable and smooth. Wouldn’t wanna be using a 4-5 year old OS X just because I was too lazy to update, or too stubborn about the apps I use, to let one or two plugins or whatnot determine the OS X version I’m on :) I remember when working at a film production company, they where talking about Final Cut Pro X just like we have been talking about Logic Pro X, and how it was not professional etc. etc. now you see soo many companies take the FCPX route, and not looking back. Why? Because all in all, it’s an easier, faster work flow with the auto-rendering etc. that’s going on in the background, the user experience is fresh and clean, and a lot of things are working under the hood much better, due to correcting the mistakes from previous editions.