This looks like you enjoy the process.
For me I aggressively follow laptop deals. For the last gen you can get competing laptops for the price of the main board alone.
Of course, I hope I'm wrong.
Buying used ThinkPads on eBay and installing Linux is closer to sustainability than buying into a new ecosystem of expensive and hard to find parts.
Or we could say “Thinkpads should be more modular, repairable, and upgradable.” Some of us want to support that approach.