Epic spent nearly a year-and-a-half giving away free games on a weekly basis (sometimes even daily) and the only thing you needed was an Epic Games Store account. Now that is about to change.
For the next few weeks (until May 21), whenever you claim a free game from the Epic Games Store, you will (periodically) also need to turn on two-factor authentication. You can turn it on here. It's a good habit to have it turned on anyway, so I see this as a good precaution against hackers.
Although it may be "a minor inconvenience for some" (as Epic describes it), it should definitely become a standard procedure for all accounts. At least in my humble opinion that is. But yeah, now that you know what Epic is planning, you can just turn that thing on and save yourself the hassle (that will come later, anyway).