After first setting foot here back in 1978, getting out of Thailand three or four times a year for a reality check is a mental health bargain. A change is as good as a rest.
Somehow, I manage to plan my life around my infrequent Thai 'outages' with consummate ease. As for rule changes, extensions aren't impervious to them either so being able to 'roll with it' isn't unique to multi-entry visa riders.
Extensions also fitted my lifestyle and served me well for the past 12 years or so. It's just that I can't be ar5ed with the immigration office faff any more.
But I appreciate that everyone's needs and opinions are unique, different and subject to change. If you are happy with longer term stays with less travel and that benefits your lifetsyle, then yes, annual extensions are (almost) perfect.