I don't get the thing about banning the stage. He literally just gets a new move he can only use on one stage. If anything the weird thing is that he can't do that on the other stages.
okay so we have random stage selection at tournaments.
wall cling is very strong, and gives vega an entire new set of oki at midscreen.
Vega player A gets spain stage luckily 2x in top 16 and is able to win both matches off of the strength of this oki to qual for winners top 8.
Vega player B who is considered a stronger player than Vega player A, doesn't get spain stage on his top 16 matches, and is playing at a deficit compared to player A because he's losing his best oki options.
It just adds needless RNG.