I'm no a local, but we have seen our fair share of that, not even during the festivals. I can only imagine it gets worse during food and wine. Generally, when planning Epcot days, I try to avoid the weekends, just for that reason. My wife will enjoy an adult beverage or two during our full day at that park, but I agree 100%, it is nice very Disney like when your teenage daughter returns from the restroom telling stories about the women passed out in the sink, and puking on the floor.
Clearly, Disney needs to do something to reign the park in a bit if they want families to continue visiting it. I'm not a huge fan of IP everywhere, and especially not when it displaces wonderful culture. I enjoy Frozen Ever After, but I am saddened by the loss of the Maelstrom, and wish that Frozen Ever After had been an addition to the park instead of displacing something else. Ratatouille I am fully behind, they are adding an attraction where there wasn't one before. There is some educational value in that it may teach kids to really enjoy good foods, and possibly even awake and interest in cooking.
Guardians of the galaxy, I am not as supportive of, unless they manage to present that in a way that continues to teach about energy.
I guess, for me at least, I am ok with IP if it is done in such a way as to continue the legacy of the park being an educational park, and is done without removing the beauty, and culture that the park presents now.
Getting the party scene, drinking till you puke theme under control wouldn't be a bad idea either. I don't mind people drinking, but paying as much as we do to go to Disney, and then watch people barfing, or have their drinks spilled on us as we walk by, etc. We can go to Six Flags and get that experience for a lot less money. There is room to improve, and I hope they do. Epcot is my absolute favorite park.