Given how long it's been out, it's about time for an updated HomePod. It would make sense since Apple's focusing on audio improvements (AirPods Pro, Macbook Pro, etc).
It's also entirely possible it's a developer error.
I think those search suggestions are based on common searches and not determined directly by Best Buy. Also, if it came as a suggestion from Best Buy, I'd expect it to have proper capitalization.
I can't see a 2nd HomePod coming out any time soon. The chip used in the current one is perfectly fine for the things it does and there's really no need for a 2nd version unless they are making a + or mini version that is... I don't think they would name a mini or + version as "HomePod 2" though.