DeletedUser127 when you disable default Phone app, you can still receive incoming calls which are handled by by Phone Services and Phone Calls system apps. There are just no means to call back with dialer missing.
My concern is that disabling the stock Phone app through the Settings UI will cause emergency calling to stop functioning. It's not clear to me if that disables emergeny calling entirely (not clear if the OP used adb or the Settings UI), but if it does (and the evidence so far suggests that it might), that's concerning to me.
Yes, users should not disable system components, but ignorant users do that all the time for arbitrary reasons, and then make posts in this forum wondering why their device is chain-crashing or whatever. I suspect they are reading posts from various arbitrary websites made by hobbyist tinkerers, or vloggers who recommend disabling what they deem "unnecessary" stuff to make their device more "private". It's not going to stop happening.