Vegeta doesn't have as many transformations as Goku, but that's simply because the Prince of All Saiyans doesn't need them.

Transformations have always been one of Dragon Ball’s most celebrated elements, the likes of which have only become more prevalent over time. Super Saiyan transformations have become the new normal, ...

Ultra Ego Vegeta may be stronger than Ultra Instinct Goku (for now), but he's hardly the strongest character in Dragon Ball ...