Bona fide market makers have an exception, because their business is to always be being buying and selling around market prices, and in a market with lots of buy interest and less sell interest, they may need to sell more shares than they normally hold. Market makers still need to have the shares in time for settlement, which may require borrowing if they have net sales more than holdings in a given day, but they don't need to locate shares to borrow before selling. Market makers are given an exception, because liquidity is valued, and they need to be registered and have specific capital requirements etc.
TL;DR, naked short selling isn't a thing anymore. There's been no reports of Gamestop shorts being naked shorts, and no reports of shares failing to deliver on time. Naked shorting isn't required for short interest to be over 100%.