For sure, that's legit too. I've had to grapple with that feeling personally. I didn't get to a great place, other than hoping that AI is democratized enough that it can benefit humanity. When I introspected deep enough, I realized I contributed to open source for two reasons, nearly equally:
1. To benefit myself with features/projects
2. To benefit others with my work
1 by itself would mean no bothering with PR, modifications, etc. It's way easier to hoard your changes than to go through the effort getting them merged upstream. 2 by itself isn't enough motivation to spend the effort getting up to speed on the codebase, testing, etc. Together though, it's powerful motivation for me.
I have to remind myself that both things are a net positive with AI training on my stuff. It's certainly not all pros (there's a lot of cons with AI too), but on the whole I think we're headed for a good destination, assuming open models continue to progress. If it ends up with winner-takes-all Anthropic or OpenAI, then that changes my calculus and will probably really piss me off. Luckily I've gotten positive value back from those companies, even considering having to pay for it.