On the other hand, courts do generally enforce click-wrap and sign-in-wrap contracts. Click-wrap contracts require that consumers click “I agree” by means of an immediately available pop-up box. See Caspi v. Microsoft Network, 323 N.J. Super. 118. Sign-in-wrap contracts include a hyperlink, often labeled as “Terms of Service” or “Terms and Conditions,” that is located by a sign-up button. Sign-in-wrap contracts require that users electronically accept the terms by clicking “I accept” or “I agree” as the last step of the sign-up process before allowing consumers to use their products or services.

Taken from https://www.law.cornell.edu/wex/adhesion_contract_%28contract_of_adhesion%29

There’s more information on that page, but essentially, no, they can in fact be legally enforced. Exceptions revolve around clauses that violate existing law or that cannot be enforced for other reasons.