1. It has negative externalities. 2. It's too expensive. 3. It's not an improvement/doesn't work.
The fascinating thing is that people see these criticisms and it counterintuitively bolsters their confidence that their tech is special, because things that turned out to be special were also criticized.
1) The number of crap things or even actively destructive things that have been criticized on these same not-so-narrow grounds are far more than the number of things that turned out to be good that got criticized. Why? Because there are far fewer good ideas than bad ones, and the bad ones get criticized more (at least on average.)
2) Not only are the listed three the only ways to criticize things, but everything is going to be criticized eventually. So, the mere presence of criticism can't be evidence of anything because everything gets criticized.