> There were regular phone numbers, you had to call these numbers with the phone (no dialer on the minitel).
That's incorrect.
There was a dialer on later versions of Minitel.
And while you could technically set up a V23 BBS-like server behind a regular phone line to talk to Minitel terminals, the whole business model relied on the use of premium short numbers (361X) whose revenue was shared between France Telecom and service providers.
It was absolutely an App Store model and fortunes were made at that time.