We do not in fact live in that world. It is not illegal to violate the terms of service of a website.
A website can block Xyz user agent, put Xyz in robots.txt, or even put "No using Xyz!" in a popup and you cannot be prosecuted for using Xyz. It might be hard for you to evade their requirements, but it's not illegal.
Whether or not it's wrong is a matter of opinion. Yours differs from mine, that's fine.
Wrong != Illegal
It is wrong to pretend you are deaf to get out of an awkward conversation. No one is going to put cuffs on you for that.
It is illegal to download copyrighted material from a website and make copies of it in violation of its licence.
I can’t go scrape New York Times articles and make copies of them without first licensing them from NYT.