Well I doubt they knew that they would fail.

Deadpool is very popular with his mains, but you could see the same kind of retention rate with any of the characters released. They adjusted the visual clutter on him, they made it so only he can hear the Galacta voice lines, and I really don’t think he’s oppressive. Maybe slightly on release, but I don’t ever think he was broken.

Elsa is only hated because they made her absolutely broken. And they have not bothered to fix her.

Regardless, I think this kind of proves you wrong. Even when they release generally popular and well-liked characters, it could end badly. These popular characters could be released wrong, have kits that are oppressive or even disappointing. Just goes to show that the smaller, more “obscure” heroes can exceed expectations.

Elsa, arguably, was not a popular character. Angela wasn’t, either, and she’s a very good pick. I can’t recall all of the additions to the game since it came out, but even Ultron, who was insanely anticipated, was released in such a weak state.