If Ed O'Bannon is on the list for what's going on in college now, then even though he didn't play in the last 25 years, Curt Flood has to be on there as well. Just about every sport has some type of free agency and a lot of the multi-millionaire athletes who can leverage their skills now owe him a thanks. Before Flood, players were looked at as property or assets by many owners.
I'll admit I'm not a big LeBron fan, but I don't think he's even ahead of Kobe or Shaq for influence. I would even say AI should be mentioned. When we have jersey day, there are still more Kobe and AI jerseys than LeBron on the kids here and about half of all the jerseys are Jordan, along with the shoes, shorts...etc.
It's hard to add Ohtani since he still hopefully has a good chunk of his career left, but as far as influence, Ichiro has had a greater impact in the last 25 years.
Jordan is the guy if the man didn't have to play. Tiger's impact can be felt worldwide. I think there was hope he'd bring more interest from black youth, but golf is still an expensive game for the most part, so it was impossible to really expect that without an economic shift. His impact on the game is undeniable. Golf courses began "Tiger proofing" to help offset his dominance.
And if we look at it worldwide, Messi, Ronoldo and Beckham have to be at least honorable mention.