The seats are assigned. People have been standing in line for 15 minutes now. Why on earth would anyone want to stand there, when they could just sit and wait until the line clears?
I understand wanting to get off a plane ASAP, but boarding? You just end up sitting on the plane, waiting for everyone else to get on.
As annoying as it is to lug a bag around and find room for it, I much prefer this to checking it. There’s the small but nonzero chance your bag doesn’t make it to your destination, plus the added time waiting at baggage return.
Yeah I avoid checking bags if I have a layover. Direct flight? Eh it’s pretty hard to fuck up then, still absolutely can, but harder. Going to a destination I hate checking because I’m eager to get going, coming home it’s just another 15-20 minutes waiting for my bag usually, so I don’t care.