If you don't want people to play your game without submitting themselves to malware and psychological manipulation, block them.

I'd agree that it is unethical to avoid things that try and stop the game from working while you run an adblocker. I signed no contract and there is no social contract that says I have to look at the ads or let all your network requests go through. To create that social contract developers need to communicate it clearly (the easiest way being to attempt to block people using adblockers from playing the game). It's not like the existence of adblockers is a secret or something.