Unearthed Arcana: Sidekicks

I appreciate this UA a lot. It allows for a lot of flexibility for players to expand their character concepts. My concern though is for the Beastmaster Rangers out there. This seems better in numerous ways and doesn’t take a character’s all-important archetype. The creature levels up with the player and all. Any class can have a pet. Doesn’t such a rule negate the real benefits of Beastmaster (besides being a creature without the various boons from the archetype itself)?