Consider it a part of your civic duty: driving up the costs of data breaches for corporations so they have an incentive to invest more heavily in security. The payouts to individuals are part of the $575 to $700 million settlement that Equifax reached with the Federal Trade Commission, the Consumer Financial Protection Bureau, and 48 states.
It's easy. It takes about three minutes. You have to give them your mailing address, phone number, and birth year, but I assure you they already know that information. They are just trying to make sure it's really you because scammers are sure to start making fake claims.