It is like when people used to call FPSs “Doom Clones.”
I think so many people have the “Roguelike-Deckbuilder-is-over-saturated” mentality because the genre is still under a decade old so it feels like everyone is still trying to ride the “Slay The Spire” hype train. It is like when people used to call FPSs “Doom Clones.” There is a lot of room for innovation in the deckbuilder genre and fans still are interested in them and there aren’t a lot of them being made (it is the second-highest by percentage chance at success). Relax.