This is definitely one of the downsides- but also possible that Google for example gets bored of one of its products and shuts it down, or acquires a product just to shut it down.
Personally I think one of the upsides is that the semi-solo team might actually decide that the successful product is "done" and move on or go into maintenance mode. IMO products like Spotify and Slack could have reached that point a while ago- sure they could still work on uptime, data compression, etc. But there is only so much you can tack onto a music player or a chatroom. They keep shipping more redesigns and new features that don't make users any better off but need to keep people busy.
I mean at sometime, you may as well just shift the engineering team onto another/newer product. Spotify could have totally made something like clubhouse.....
Personally I think one of the upsides is that the semi-solo team might actually decide that the successful product is "done" and move on or go into maintenance mode. IMO products like Spotify and Slack could have reached that point a while ago- sure they could still work on uptime, data compression, etc. But there is only so much you can tack onto a music player or a chatroom. They keep shipping more redesigns and new features that don't make users any better off but need to keep people busy.