Not to pick on you specifically but, for a lot of people, bring less stuff. I don't use a roll-a-board for carry-on. I travel with fully legal soft-sided luggage that doesn't inflexibly take up as much space and a small computer bag. I rarely find I need to check luggage unless I'm doing activities that require sporting gear etc.
Airlines are partially to blame for this behavior as well, since they rarely enforce it or even give much guidance. People also walk very slowly into the plane, struggle to lift their stuff, then realize they need something out of the pocket so they hold up everyone while they get it. I also never understood why both doors aren't used for boarding and the planes boarded middle-first.
I bet I could get the boarding time down to about 40% of what it is right now with my suggested changes. In the security lines, there are too few lanes open and too few helpers. If I opt out of the idiot scanner, it adds at least 10 minutes, sometimes 30. I've had many TSA people be incredibly rude to me when I've opted out, one yelling at me for putting my carry on in front of another person's on the undriven, too-short conveyor belt after the same person had previously instructed me to remove my bag from the belt when I informed them I was opt-out (every other time I've flown, they make you wait like an idiot while your bag and the contents of your pockets sit on the other side of the conveyor, free for anyone else to take).
The security theatre on display is also infuriating. If one wanted to, travel with someone and have them not opt out, but grab your carry-on from the other side of the scanner while you wait for them to even call for someone to think about coming over to check the elastic in your underwear for a wine opener, which if they didn't confiscate, would have obviously been used to initialize the downfall of western civilization. Meanwhile, the random checks with guns in their pants get through the blow-hard machine all the time: https://www.google.com/amp/s/amp.cnn.com/cnn/2015/06/01/poli...
My guess is that this is of no real benefit. Refueling, restocking, loading baggage, running maintenance checks, and other tasks need to happen before the airline can get the plane back into the air. Only extremely infrequently have I been on a plane that was able to roll back from the gate shortly after the last passenger boarded.
If the limiting factor here was passenger boarding times, airlines would have every incentive to improve the situation from where it is now. They have no incentive to speed up boarding to be any faster than the slowest of the rest of the preflight processes.
You definitely fly in comfort as a business passenger, but I wouldn't say you fly much more efficiently.