The startup where I worked had 1 million downloads (which is much less), but how many of those were using it daily vs trying it for 30 minutes and forgetting about it?

Less than 10% in our case :)

1 billion downloads, even if only 10% of those are active users, is a massive number.

Heck, I haven't even downloaded the ChatGPT app, but I use their website all the time.

AI use has taken off, and a large fraction of the population is using it regularly, if their own accord.

Yep, the free tier. Will they pay for it or stick around once it becomes more ads than anything else?

My point was that using something heavily means you have an informed opinion about hating it. Hating something you have never tried is way weirder.