Seems like a response I would give to my dumb clients too.

Some people are just too dumb. :))

I love that last sentence "Use some common sense man." 😂

the developer should have restricted the app to not be downloadable from OP3 phones...

Yes people are stupid but insulting a user is one of the worst ways to deal with such users. You don't need to insult them for them to get the message. You can explicitly explain the use of this app. And change the title adding (for non op3 phones)