Yeah everytime someone says "just learn COBOL, you'll make tons of money," it's like,

Bro.

There's a reason no one wants to write new software in these languages anymore, let alone maintain a forty-year-old pile of technical debt.

Been working in COBOL for a decade and this is all true.

I'm lucky. I personally enjoy it. But i can totally see how it's an absolute nightmare for most people.

I've been meaning to learn Fortran in part because because of the whole "big bucks for being willing to maintain old software" thing, but mostly because I'd like to work on the sorts of scientific computing software that was (and still often is) written in Fortran.

COBOL isn't too terrible, it has its gotchas (like sizing variables for inputs (in which you don't need space for the datas headers and will break stuff if you do)) but mostly it's an old language designed to be easy to use

New staff in my workplace first using COBOL (with other build experience) learn it to the point they're productive in a week or two

Yeah man I'll take plain old php and java any time of day, I can still get enough money from it to pay my lifestyle. And at 5pm I can close my laptop and play vidya with no worries.