First, the allies referred to the Panzer as a specific tank model.
Secondly, actually what was relevant was that the allies prevented the Germans from having air superiority. The US and English planes were not decisive in the break out... however, if the Germans had had free air reign over the battlefield then they might have pushed the allies back. There is a distinction.
Third, as to the allied bombing campaign to f' up the germans in any way possible... sure. Total war. If the NAZIs had not been driven back they would have gotten nuked. Count on it.
As to the effectiveness of combined arms... of course. Often the allies would break a german fixed defense with artillery, dive bombers, or infantry. Just because I say the Sherman is underrated and the tank crews suffered fewer losses than any other tank in service in the war on either side... that doesn't mean they were the only relevant weapon. Everything matters. I'm just saying the Sherman was actually quite good at doing what it was designed to do which was charge fixed defenses and/or engage german tanks.
Did the Sherman have an inferior gun to the Germans? Sure. But it had superior mobility. And something that is not appreciated is that the German armor while thick in material was actually designed very poorly. They didn't slope their armor. Their tanks were full of these flat perpendicular surfaces which would have been vastly better defended if they were sloped or if they just wanted to retain the same defense they could have radically cut the weight by sloping the armor.
The Sherman had sloped armor. If you look at the front armor... The gladius on the Sherman had an effective 47"s of armor. And that's what you point at the enemy tanks. That's roughly similar to the fucking tiger itself.
Did the germans have bigger guns? Sure. And german guns shooting at german tanks would have seen the german guns go through the german tanks as easily as the US tanks.
The difference was that the US tanks were remarkably lighter which made them faster and more manuverable and thus better able to attack and retreat.
Did Shermans often need to hit enemy tanks on the sides to breach them? Yes. But frankly that wasn't uncommon. A lot of shots would bounce off the front of a sherman as well. Most of the bad damage you see on shermans is on their SIDES just like the german tanks.
The formative work on this whole "shermans are shit" argument is a book from a guy that was tasked during WW2 to look at battle damage to KILLED sherman tanks. That's who that guy was... he wasn't in the battles. He didn't see the shots bouncing off the tanks. He was looking at dead US tanks after the battles. And what he also wasn't taking into consideration was that very few of the US tankers were actually dying in those hits when compared to the Germans and Russians.
The US tanks had excellent escape hatches. They opened quickly and were right in front of the tankers so they could just get the fuck out. And when they got out they had their helmets on and everything.
There were stories of US tankers that would lose several tanks in a day. That is, the same poor bastard would go out in a tank... get it destroyed... escape it... come back to base... get a new tank... rise and repeat three or four times in a day. That didn't happen in any other service because other people didn't survive that kind of punishment.
Were a lot of Shermans lost in some battles? Yep. Especially the "hedge rows" out of Normandy were a nightmare. But a lot of that was about poor maneuverability because of the hedge rows as well as poor visibility because of the hedge rows. That was a worst case scenario and its sort of like judging how effective a deep sea war ship is when it has to fight in shallow reefs. I mean, you can do it... its just not a great idea.
The Sherman had a problem in the hedge rows when it was employed alone. It did very well when it was used with combined arms of air power, infantry, and especially heavy artillery.
In practice, the first tank to hit another tank in WW2 WON that tank duel. Even if the first shot didn't penetrate. The tank that would fire first often would land a second shot before the first tank even got its first shot off.