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While artists' designs are the least of my concerns in the Pokemon series and at least bother to create a design, it's not to say monster design hasn't declined over the years.
Because it totally has, but only for the sake of regional padding, which isn't particularly impressive but still is rather plain. It's a variant, but the design is essentially the same with very slight changes.
tl;dr don't come at me shoving Sword and Shield as if they gave 70+ '''entirely''' new pokemon.