I regret building it, but not for any ethical reasons, except for maybe that it's become nothing but corporate ads.
My real reason for regret is just the entire process that happened after it became successful. It took off and was over 50k DAUs ~5 months after I launched it. I tried supporting it the best I could, and had aspirations for the future of it, but I was young and dumb. I got caught up on feedback, took it too personally and started having trouble in my personal life due to it.
I ended up selling it to another company for far less than what it was worth, even while I had 2 competing bids because I let one of them get to me emotionally at the time. I also agreed to continue working with them on it, at what I found out later was vastly underpaid, to the tune of being ~10k below the CA minimum for a salaried SWE. Our time together lasted less than 9 months for a myriad of reasons.
I regret it, mainly because I always look back and think of what could have become if I had the strength to continue it solo, or had spent the time to look for a better partner to carry my vision forward. Instead now, you can get your latest [insert corporate media here] watchface from it for a mere $4.99/mo.