What do you use it for?

If you buy one soon, it will probably come standard with the White Paper written into the OS. Sorry, that is about all I know though!

Use the old one as a bitcoin full node

That the m1/m2 is awesome but can also be a compatibility nuisance even after all this time.

It doesn't get better than 2013 macbooks

and run a node on the old one?

Max the ram for the model that suits you best.

The M2 Air, maxed out as you like is a very respectable machine and friendly on the lap or in the bag.

Really anything with Apple Silicon will be a major improvement. Even the low end Air.

Get a Chromebook or Chromebox like I did in 2021 after 20 years of MacOS (that I still enjoy very much at the office)