I would so love it if they brought back the sizers, not the metal open squares, to check bags. I thought the main issue with them at the x-ray machines was different airlines have different sizes?

I think they will be much more strict about carryons. If they are the proper size, they will not charge you to gate check assuming you don't have more then you should. If they just run out of space, if it's a wheelchair or stroller, they shouldn't charge.

If it's too large to be a real carry on, if you have too many, then they should charge you.

But they shouldn't charge because the plane is full and there isn't enough space because nobody but me puts their pack under the seat in front of me (mainly because I don't want to get up to get stuff later).