How do you plan on getting on when packages from PyPi stop supporting Python 2 at all? When Django, flask, numpy, requests, pandas, and more just don't even install? Will you just use ancient versions?
Scheme that I wrote in the 1980s still runs (and is running today in commercial systems). I have so little patience at this point for this "higher version = better" nonsense.
If you're only doing algebra on an air gapped computer then why do you even worry? Programming languages and tools will evolve but nobody is forcing you to. Keep a local copy of what you need and be happy. Just don't assume any new libraries you might need will support your stack forever.