[VorpalWay]

Define production. Docker compose is fine for running a small internal service in production for dozens of users (i.e. not for developing said service, but for using it). I would assume it isn't fine to run a hyperscaler (but I wouldn't know). Those are extremes, and there are going to be a ton of situations in between.

I can't personally speak to what the limit of docker compose is, as I have only worked on the lower end of this: self hosting for personal use and for small internal services serving maybe 20 users.

[Ronsenshi]

From my personal experience if deployment strategy is thought through then Docker running through Compose can handle few hundreds of thousand of users per day without an issue and probably could handle more with proper hardware upgrades.