Non-disclosure agreements which are overly broad have been getting overturned.
However, this is a liability indemnification, which is entirely different, and might be enforceable despite its breath-taking breadth. You do not want to face the costs of litigation defense, which has zero upside.
For example, look up the old thread about the NDA and liability indemnification which Vinotemp got its customers to sign blithely.
Of course, I am just a poor Chinatown noodle-slinger, not a lawyer.