No, this won't "change the industry". Cross-overs have been regulated to the comic world (and Stephen King) for good reason; mainly the reason you yourself stated. Cross-overs often make the visiting character feel watered down and stale, because there's just not enough time to expound on both their characters. Now, in the Netflix world where a bevy of movies is at people's finger tips, enjoyment of these types of movies still rest on several factors.
First and foremost is the amount of free time needed to watch all the movies necessary. They may be available, but that doesn't mean everyone's going to have time to watch them all to get the full enjoyment. Second, even cross-overs in comics feel like bad fan-fic ("Guys, who would win in a fight? Hulk or Thor?"). They just feel like ridiculous tie-ins for directors/writers to shoe-horn in free advertisement for other franchises, and I really don't wanna see Ryan Reynolds swoop in to save Batman from Bane.
Finally, and most importantly, it tends to take away from the gravity of future situations when several franchises that consist of "the world's gonna end, and only this guy can save it" come together like this. Now there's no sense of danger because if, say, Captain America looks like he's going to fail in CA 2, then so what? Call up Thor, or Iron Man, or any of these other apparently capable people. It diminishes the Hero's Journey story type because now there's not just one Hero the people can call on, there's many. And, like Bob said, "How's Stark gonna act now that he hung out with a living god?" His character's gonna regress because there's literally nothing that could be as threatening or interesting.
TL;DR Avengers won't change the game for the film industry. In fact, I'm betting the Marvel movies decline in sales (and probably quality) after the Avengers.
