You never know how much crap you have until you physically have to move it. Even if you’re organized, and have all the stuff you swear you’ll use/need/look at/read/watch/listen to again someday in boxes and crates and such, a lot of crap is still…a lot of crap.
Unpacking is made easier when you unload in an organized fashion. Otherwise, your large, 2-car garage looks like it should be part of that Hoarders episode where there’s an intervention and the person breaks down and cries because that old dude just won’t get rid of anything (isn’t that actually EVERY episode of that show?).
Finding anything after a move, whilst unpacking and getting organized is a VICTORY and makes you feel like you’re actually makind progress.
If you think it won’t fit thru the door, it probably won’t.