The interviewer's fear is always the same: that if I take the position, I'll be leaving shortly in order to start another venture. I explain (and point out in my work history) that isn't the case. I don't take permanent positions with the idea that they're temporary. If I wanted a temporary position, I'd do contract work instead.
I don't know if this aspect of my work history has ever cost me a job, but if so, it doesn't matter. I land jobs anyway.
Real programmers hiring more team members see side developments as a strength, they only want their work to get done.
Assuming you're like the rest of us and have material needs and bills to pay, it's not even a lie. :)
I have been on 2 teams where a member had a 'tech' side business. They spent each seemed to spend 4 to 8 hours a week on their side hustle, while supposedly working at their job.
I currently have a co-worker (we do not work on a team together), who has a side business with his family doing indie games, but I have never seen him work on it at work.
A full time programmer, even one who sticks around for 8 months or so, is far better than a contractor. There's also the possibility they hang around for years.
Someone who's doing indie work on the side, well, they're upskilling themselves at least. And they're more likely to be incentivized by more time off or less work than they are by more money, so it's not always bad.