I look at it now, and...well, I'm all-in on k8s for most things, and cloud functions for most everything else, so I'm really not sure what the advantage of using Heroku would ever be if it they don't have a free plan.

For free databases there are multiple options like CockroachDB and Supabase; throw up a $6/month droplet at DigitalOcean and you get the equivalent of a $50/month dyno at Heroku. Yes it's easier to deploy to Heroku, but it's only a couple hours to set up some kind of CI/CD deploy, and then you can control it more precisely.

Heroku has basically been a "first one is free, but as soon as the business gets big, soak them" company from the start. Given the number of companies offering free levels of cloud functions and hosting, I think that's where most new experimental development will migrate to in the future.

I sympathize with them for giving up in the fight against abuse of their free services, but ... well, I think they're likely to transition to irrelevance if they don't pivot or slash prices soon.