It’s more convenient than Lutris for installing adhoc games, or multiple games in one bottle. Don’t get me wrong, when Lutris works out of the box it’s great, but oftentimes there’s no recipe on Lutris for a game (eg when they’re relatively unknown or new games) or the recipe is severely dated.

Honestly I’m not totally sure, I’ve heard that it handles sand boxing differently but I don’t know the details

I just know that on occasion I’ve had some windows programs fail to install while using lutris, and I’ve tried bottles and it worked, I probably could still get it to work in lutris if I tried, but It works most of the time in my experience so It’s the first piece of troubleshooting I try

I find that Bottles is more like just setting up your own wine prefix and keeping it organized. I was a Lutris user for years, but switched to Bottles last year and never looked back.