Technically no, but that falls under “ignorance of the law is no excuse” area.
If we choose the easy way out, then it’s no one’s fault but our own.
And then you end up with twats crying that they or their lords and saviors get booted from private websites, because they didn’t bother to read the contract and the rules that must be followed.
If however, it’s proved that the company offering the contract took specific action to deceive us or hide the contract or coerce us into signing it, then we have a different ballgame.