HomePod Dolby Atmos without Apple TV

I have three (3) questions.

1. Can HomePods (not minis) connect with other smart TVs (without the Apple TV box)?
2. If so, can the HomePods still sync and produce the Dolby Atmos surround sound?
3. If not, does the HomePod Dolby Atmos surround sound only work via Apple TV App tvs (i.e. no Apple TV box)?

I ask because the Dolby Atmos website made a mention about the Apple TV App, but I'm not sure if this means it skips the need for an HDMI ARC port. Since the Apple TV App is now on "other tvs," then the Dolby Atmos surround sound should theoretically work. Trying to get some use case requirement confirmations.