You're also affecting those who already got him for free 3 years ago. If people really wanted him, he should be available in treasure of the sages. If you put it there, you don't give up any other ninjas that can be potential given for free or not in a redeemable prize that fits in the current meta. Really old ninjas should not be taking up spots in events where they usually give out relatively new or brand new ninjas. Treasure of the sages is the only event I can think of that includes old ninjas on a regular basis. Since Oasis likes to repeat ninjas in daily-sign in he could also show up there as well.

Also, the only people who said he was meta are from people who didn't have any other ninjas. Even with shisui, he was easy to deal with.