That's certainly debatable as to whether or not that revenue is significant or not.
Ohtani is really the only Asian player we have heard about generating a ton of additonal revenue, beyond what is typical for a major league star. Maybe there was some chirping about Ichiro and Matsui back in their heydays. But Ohtani is primarily the only one we hear about now. However, he is the best baseball player on the planet, so comparing him to other Asian players seems silly.
Yes, Imai is a reasonable gamble as a 27 year old starting pitcher that has MOR potential (or better). I was only arguing against the point that the additional revenue might pay for the contract itself, because again, that only applies if he is good.