I am glad it works for you. Maybe (hopefully?) I have just had an abnormal experience.

I'd say I can get behind pair-programming to a point... it helps get new ideas, different view points and leads to rubber-duck-programming like effects.

I'm not sure I'm a fan of Mob programming... as others mention, over a phone/video conference, it seems inadequate. Turns more into an ad-hoc video lesson by the stronger personalities (for better or worse - I happen to be one of those in my small group at work).

Do you have problems with both? 2 vs 3+? or is it one or the other?

To do mobbing effectively you should be switching the driver very rapidly. It's a bit tough remotely, but it can be done. There are probably other ways to make it effective, but if only a few people are contributing, then the mob has failed and should either be recalibrated or stopped altogether.

No, anecdotally a lot of people struggle. It is an intensive experience and places different pressure on a person than soloing does. For me it works great, for many people it works great, but not for everybody.