If you own the .com, you can use any domain or any gTLD you like and not be hurt by it. It can even help.
However, if you don't own the .com, you will lose traffic. You will pay a penalty for all your ad costs. You will pay a penalty for customers lost.
You will pay a penalty because your business growth may be stunted or not even there. They have been sucked up by those extra costs that would generally be used to grow your business. The money you might have actually put in your pocket as profits.
If you get waterproof.shoes you MUST own waterproofshoes.com. You must! At some point you either will own it or go out of business. The guy that owns waterproofshoes.com is gonna make more than you with no expense. YOU are paying for HIS advertising. THAT is why the .com will benefit from .whatever. Folks can argue the point, it won't make them any closer to being right. It is so obvious that anyone doing this as long as we have should understand it. I am glad the end-user won't. That will make me a fortune and you too!
Do a test. Tell 100 folks by word of mouth and see how many get it right. You will be stunned!
So hope Madison Ave buys into .whatever. I hope they all do. There is no downside for .com but there is a HUGE upside. Huge!
Put waterproof.shoes in a Superbowl commercial and waterproofshoes.com will have a record day. Guaranteed! He is growing for doing nothing. Getting advertising he could never afford. It is going to be a windfall for .com the likes of which you could only dream about.
Every startup wants their .com when they grow up.
So here is my next prediction. Most of the domainers that lost in .com will try .whatever and see it is even harder. They will get angrier and more frustrated and will lash out in ways we have never seen before. Why? Because they still don't get it. They still don't know the difference between tin and gold, glass and diamonds, water and poison. They will get angry at me for their own shortfalls instead of learning and grabbing their share of the pie.