I go the other way. No docker, just bare metal server with 4 cores and it can handle a shitton of traffic.
- Debian OS, fully locked down (all ports closed except SSH, with limiter).
- SSH + rsync to deploy app. I don't have a risk factor of managing dependencies between dev and prod, so I eliminated docker.
- SQLite db that gets thrown on S3 every hour using a python script. I don't want streaming anything. Just hourly backups is good enough.
- Cloudflare tunnel to connect to outside world and serve requests.
It is fast, cheap and requires not much "infra" knowledge. Of course this is for solo devs and small companies.