What market is stagnant? There is a pretty lively (I would argue TOO lively) market in domains: both registering new ones, and trading old ones.
IN what way is creating more TLDs innovation? Inventing DNS was innovation, this is not.
Given they will be effectively purely privately owned by the likes of Google, any other business using seems to be taking a big risk that the rules may change in nasty ways. I know that I can move a .com or a .co.uk between competing registrars, and there are clear rules about things like trademark disputes. Google running a TLD without oversight cannot offer the same.