They used to have a free tier that they killed out of the blue [0]. The cautionary tale is that you cannot just trust these services, they might change the rules at any given time... You can however learn to deploy your own servers and manage your deployments with FOSS tools like the ones I reference.

0: https://help.heroku.com/RSBRUH58/removal-of-heroku-free-prod...

no, Heroku is fine, as long as you have a basic understanding. If your service becomes a runaway hit, your heroku bill may get big, I assume that's what OP is referring to.

It's just expensive and is less of a value add than it was when deployment tools were painful (especially for Rails applications)