I see this sentiment a lot and I don't really agree with it at all. The changes at DHS and Epcot aren't making it like the MK at all. MK is set up with distinct, well defined lands with attractions that by and large compliment each other. Sure, Tomorrowland is a bit of a mess, but otherwise it's quite cohesive and isn't overrun by IPs the way people seem to always suggest. The most recent change to MK with the FLE actually tightened up the theming there.
DHS is going down a path of "experience the movies" with franchise driven lands. The front of the park has retained an entertainment celebration vibe. These things are quite distinct from MK which uses more generic tropes to define the lands and individual franchises have at most small sections. If anything, a better argument would be made that the addition of Star Wars is making DL more like DHS.
Who knows what Epcot will end up as, but the more it seems like a random hodgepodge, the less it is like MK.
I'd actually be totally for another theme park that was similar in structure with MK, but with different themes for the lands. That's basically what TDS did and it compliments TDL, rather than be accused of copying it.