I had the same thought, but more as an illustration of why the approval process worked exactly as Apple would like here: they likely want to establish a barrier against whimsical provocative marketing but not against serious app development.

If you're willing to make a serious case for why your app is called "Heroin" they might approve it. If you're clearly doing it to make a point, they have every incentive to censor it.

Why can’t you call an app heroin?

Genuine question. Is it somehow going to cause more drug use? By what mechanism?

Why do we accept censorship so easily? Is free speech not worth more?

For the record I'm not a fan of this sort of censorship either.

But I'm guessing their aversion to drug references is more to avoid offending people than to discourage drug use: opiate (and amphetamine) abuse is a pretty serious problem around the world, and a lot of people have lost family or years of their own lives to addiction. Naming an app after something with so much destructive potential---and as a marketing gimmick, no less---might seem a bit insensitive to some of these people.

Again, I'm not saying I agree with this logic, but it's a perspective to be mindful of.

You're not guaranteed free speech by private corps, they're not a government after all.

I don't have a problem with any of those names but it's their policy which developers agree to before publishing apps.

Next, ban synthesizers producing acid sounds. So long, TB-303 emulator:

https://apps.apple.com/us/app/pure-acid/id1481283602