We're at war!
If we remain hydrated, the terrorists win!
Security if going to be backed up far enough without having to check to see that a bunch of people's bottles are actually empty.
Beverages are served on the planes. You don't have to worry about dying of thirst on the airplane.
As for while you're in the terminal, just get a drink at that fountain at which you were planning on filling your water bottle.
You're complaining about nothing of any significance.
You aren't being kept from remaining hydrated, or even significantly inconvenienced. You're complaining because you can't do exactly what you want in the way which you want to do it.
This is effective only at teaching people to be sheep for a police state.
They have solid evidence of a viable threat.
Due to that they are limiting taking fluids and gels on as carry-ons to those who have a clear NEED to have them, such as infants with formula. They can take the time to test the fluids for those relatively few people without the security grinding to a standstill. They cannot spend time dealing with each and every person that might want to carry on a bottle of water.
That's reality. Deal with it.
They aren't infringing on your rights. They aren't making unreasonable demands. They are simply responding to solid evidence that a threat of this type exists currently.
I'm sorry that the airlines and airport security, during a time of war, cannot accommodate your every desire to do things the way you want to do them.
However, maybe you should find something more significant to complain about than not being able to carry your preferred water bottle through security rather than drinking the water provided on the plane.