.com isn't going away. I was around during the .co hype, when speculators thought companies would move to .co from .com because it's shorter and co is a common abbreviation of "company."
The "problem" is that .com is so integrated with commercial professionalism and the Internet experience that we're thrown off when we don't see it in the address to a website. There's no reason for anyone who uses a .com to move away from it, and because all the corporate giants are using it it will be the go-to for newer businesses to establish themselves on the market.
Domainers love the idea of a new TLD taking off, because it's effectively a reset where they can apply their expertise and catch the good ones, but it's not going to happen. Even China couldn't get away from the .com, and only 1% of the Chinese population speak English.