One of my coworkers is a retired lady in her mid 70s doing COBOL as a freelancer.

Many projects are still running Perl applications but failed to train personnel.

The only drawback might theoretically be the need to show flexibility and move to a new location.

But truth is that mentioned lady is now working 100% remotely.

I'd say conditions for elderly experts are getting better and better recently .. :)

All the best!

PS: and if you are just looking for an occupation, schools are desperately hiring even untrained teachers to provide IT courses.