There are two markets. One is this means that you can make software for cheaper. What software didn't exist because it was too expensive to create? Nevermind finding a team in India or Eastern Europe, you can now make a US team and pay them in equity until you get funding/revenue. What underserved niche does your mom/wife/girlfriend/boyfriend/dog currently not have software for, that they'd be worth a couple of bucks for? What niche, existing piece of software is out there that currently sucks?
The other market is this cohort themselves. What will "40 year old software engineers without a job" pay for? Food, rent, gym membership, haircuts, Factorio. Figure out something they want/need (other than jobs) that they'll pay for, and make that.