wareyathe only thing out of place with pyro is the specific pair of combos axtinguisher/flare with degreaser in specific zoning situations; I never said anything about the rift axe or the bubblegun because consistency and art style have absolutely nothing to do with gameplay so even considering that for what I'm saying is fucking retarded.
out of place is in terms of gameplay; debuffs like jarate milk and bleeding make sense because they're similar to afterburn which was an original part of the game; being able to deny and punish any engagment except for super specific ones is completely unique and not considered in tf2's original balance design, so reasonable counters don't exist like they do for other aspects of the game that do that kind of denial. sentries, you have stickies and pipebombs and most classes can spam at them - they're stationary, immobile (originally) and you don't have to worry about them outside of vital chokes; heavies you have spies and snipers, and other classes can spam them down given (I'm going to stop mentioning spy because they're a general special counter that's countered by everything else); sticky traps have a very small area of power and can be knocked around and shot out and ubered through; none of these things are out of place because there's proper compensation for them in other parts of the game. pyro's situational utter denial isn't. it was tacked on and buffed to hell and given toys and not properly tested.
The solution to getting past a pyro is killing it. Not as hard as you think except on some rare maps at specific places which you should scout in advance. You're exaggerating the ability for pyros to deny an area so much. You know how to get past a heavy that's deny an area? Killing it or hurting it to the point where it can't stay. How to get past a sentry gun? Shoot it down. How to get past a pyro? Kill it. Just because airblast was added later and doesn't something new doesn't make it out of place. That being said, minicrits were totally out of place when introduced. No falloff damage and damage buff? Nothing was even close to that effect during the time. Well placed stickies aren't counterable by anything but uber or going away because they can be continually thrown into the area again (like pyro). And the demos don't even have to be close, where the pyro is at risk of dying. Also, you mention sentries deny vital chokes; so do pyros. Outside of close quarters they suck.
Just try running an ubered heavy into a pyro. If you're competent, the pyro is dead during the 2nd airblast. If you're a competent soldier, you can shotgun the pyro or wait for an airblast and shoot after and kill it with two rockets. Demos can force pyros to lose so much ammo by spamming stickies at them. Scouts can twoshot pyros if the pyro can airblast them, and also have the ability to move away after a single airblast if they didn't jump beforehand. I feel like you're trying to compare a pyro that will perfectly airblast at point blank every single rocket fired when in reality two soldiers shooting at a pyro desynced will kill it, demos will eat away the pyro's ammo like nothing, and scouts will twoshot a pyro or back away depending on the situation (fine for that matchup), and ubers will destroy pyros with basically any class.