I'm in my fifties and had no interest in bmx until I found this 2001 Diamond Back on a trash heap. I'm 6' 230 lbs. The seatpost is long so you can sit and pedal but standing up you get a lot of power for quick acceleration. I use it for short commutes or take it on the skytrain to boot around town. I live on top of a ridge so it's downhill into town I can throw it in a cab or on a bus back up or ride and walk up hills.
Bmx bikes can be set up for trick, racing or cruising. They can be heavy steel like mine or light aluminum, they can have long or short wheelbase they can be $50 beaters or $1, 000 and more precision devices. Modern bmx have a three piece crank you can change front sprocket to suit your needs. I notice some of the racers ride their bikes to the races and switch out crank arms. Pretty easy to have a couple of different sprockets and crank arms in a backpack with tools and change parts as conditions change. So how can you say you can't commute on bmx? as which type? how equipped?. I have noticed you can buy tall touring bmx seatposts equipped with water bottle holders. Number 1 reason to ride bmx? You will look way cooler riding any bmx bike compared to any other type!