Red Velvet not touring is so bizzare to me. I don't think they can do stadiums, but they could definitely do arenas. Like ffs, Mamamoo did an Arena tour
Maybe it's like f(x) since I think they only ever had like one concert. SM just doesn't like some of their girl groups touring much or maybe they put all their investment into their "main" girl group touring. So instead of Red Velvet, they are pushing Aespa.