Great advice here. So called "experienced cyclists" opinions are as subject to scrutiny as anyone else's...maybe more. Be comfortable on your bike, love your bike and ignore the rest.

Yes, you have a lower gear with 650...but that's why we have gears.
IMO...Compact mainly means you have fewer high gears, not that you are lacking a high gear. 50x11,12. You just get into midrange gears earlier 50x14 etc.

Exhibit A. Mirinda Carfrae 2010 IronMan world champ on 650 wheels. Guaranteed she wouldn't have been on 650 if it was slower.