DigitalOcean App Platform

Is it just me, or is $15/mo for the cheapest Postgres-with-backups a bit steep? Heroku's free DBs (or $9/mo basic plan) support daily backups.

I've currently got a web app I'm just self-hosting on a DO VPS for $5/month. I have a Postgres DB on the same VPS (via a Docker image), with a 10-line shell script & cron job for backups to Backblaze B2 (which costs ~nothing/month for my tiny DB).

Additionally, my web app is a Kotlin API and a Nuxt.js SSR server, so I think I'd have to set it up as two separate "apps" on this platform. That means I'd be going from $5/mo to $25/mo.

On one hand, that's not a ton in the grand scheme of things. On the other hand, the whole reason I use DigitalOcean and self manage my infrastructure is to _not_ have to pay that kind of money for my projects with no revenue.

I think you're stating the reasons already. There are people who don't want to self manage. They want a fully managed solution and don't want to think about the ops.