You can sell carpentry work directly to people in your community as an individual, and make a profit on every customer. Programming needs a larger customer base to break even, and you generally won't be selling software to individuals.
These companies are running on fumes. They cut to the bone, through the bone, and everything is being held together by a thread.
But security research is really far removed from the skillset of a startup app developer. Realistically, even if you were capable of learning, which most aren't, it'd take longer for you to get up to speed than it would take for the market to improve.
The more relevant answer would be to bootstrap an MVP and pitch it to investors to get funding to scale. There's no piecework model for consumers like "install can lights" or "build a she-shed."