Sure. But thing is, there's software out there for which FOSS doesn't even make much sense.

I'm talking things that are so niche, the total amount of potential users (not customers - that's a much smaller number) is in the hundreds of thousands, not even millions - most of whom have no say in what software they use, nor does it affect their pay checks.

If I was building, say, accounting software that every company can use, that'd be different, because while still business focused, there'd be a lot more grass roots interest in it. But I'm talking about software where you have to sell it to a bunch of execs, along with support contracts and uptime guarantees, because their entire business is dependent on it functioning properly. I'm also talking about software for one niche of one industry in one country.

The project isn't useful enough to you, an engineer, to reverse engineer the backend. Nor are there any open alternatives that work. It requires keeping up with regulations, including some that change every year. It's not that the software itself is super complex magic, it's that it stops being useful if not well-maintained.

What I have considered, though, is making parts of it open source, and keeping only the "secret sauce" proprietary. The open source parts would be stuff that could be used to build similar software for other niches of the same target industry, whereas the super specific niche stuff and all the regulation compliance stuff (much of which is just for that one niche anyway - other niches have different regulations) would be proprietary. Essentially building a set of FOSS libraries, and a niche proprietary application that uses them to service a specific market. Again, good reason for using a forge where you can have both public and private projects - but of course I could just use CodeBerg for the open source and host the rest of it privately.

I'm only building this in my spare time and fairly slowly because I have to do work that gets me paid though. I don't know if I'll ever have an MVP I could show investors or clients.

You:

That was somewhat facetious and self-aggrandizing

Also you:

I’m the person who’s going to crack and redistribute your shit as soon as you publish it, nice to meet you :)