Surpassing Ohtani won't happen for a while, but over a 30-year span it's possible
Honestly, I don't think one will emerge for quite some time, but looking over a 30-year span, there's a possibility that a “monster” who surpasses Ohtani could appear, with Ohtani's presence becoming the benchmark. If it's about surpassing in terms of contract size, I think it would only happen when the overall MLB broadcast rights business and the Japanese/Asian market size make another leap, and when a player who fits that wave emerges.