That makes sense, and would explain my August lock/bridge issue. I recently got a HomePod mini, but I have it right next to the Apple TV, so it's not helping connectivity right now. I might move it to another part of the house so it can be the hub, or share the hub-ness with the Apple TV.
For a few months, I didn't have either (I sold the HD version to upgrade to the 4K one), and had to use an iPad Pro as a hub (centered in the house); it was worse. The HomePod mini helped a bit; the Apple TV helped more, even thought it's by the HomePod mini.