It is reasonably predictable for most situations how a judge would rule, which is why contracts have common boilerplate.
In the event that one part of the contract is nullified, it's up to the court to determine if that modification will nullify the contract or not, it depends on the circumstances.
The presence of the clause cannot prevent to cancel the contract, the absence of the clause doesn't mean that the contract is cancelled if any clause is found invalid.
If you want to escape a contract, you need to go to court and make a case that the contract should be nullified.
If you want to cancel a part of a contract, you need to go to court and make a case that a part of the contract should be nullified.
They are 2 completely different things. The clause is irrelevant, it's not gonna change your future strategy.