Sweeney Todd et al (as you mentioned in your examples of thriving NEW productions) are old news here in the U.S. and have been done in their original form
If you want to decry the end of theater as we know it by blaming Disney...fine...but please come up with some better examples of how NEW theatrical productions are thriving elsewhere in the world...or haven't you heard that Sweeney was first done in 1979?