I can see a good arguments for Serena giving Tiger a fight. Over the past 20 years, Tiger's probably had more bad publicity than good, which doesn't help his case.
If the criterion was last 30 years, it would definitely be Tiger, then Jordan. But Jordan didn't do much of anything in past 25 years. And Tiger was already a phenomenon by 2000. Serena did all her work in the 2000s. And she's still relevant enough to make news by appearing with Kendrick at the Super Bowl.
I'd say LeBron is third, Clark and Ohtani would fill out top 5.