Have you tried it yourself? Your guess is as good as ours really
People will eventually try it if they have a legitimate use case for it. I know @joffreyjaffeux is a fan of Heroku so he might give it a shot at some point in the indeterminate future.
Hello, currently to use Redis addon, you need account validation using credit card, which I haven’t done already. So @joffreyjaffeux may check into that.