TR maxxis tires hold air without sealant??
Not for long. I ran a pair of Specialized tubeless ready (or whatever they called it then) about 5 years ago mistakenly thinking that were UST. I had to pump them up several times in a hour to get me home. Some tubeless ready have pretty thick ribber casings and will hold for a while but they do require some sealant to stay inflated for any length of time.
UST stamped tires have a butyl layer inside so they don't require any sealant. I had an issue getting a Hans Dampf seated too but that was on a non UST, non tubeless ready converted rim. Other tires were hard to inflate on those rims too. Usually Schwalbe tires do air up fine.
Sometimes the valves clog up so that air can't get in fast enough to inflate the tire. Try removing the valve core, airing up and then putting the care back in. I learned from someone here to drop some tri flow onto the valve core to help keep it from clogging with Stan's.
Debate? Bikes are made for riding not pushing.