Apple HomePod quietly moves from iOS to tvOS after recent update

In our hands-on review of the HomePod, we found its audio performance undeniably powerful, rich and sharp, crushing the competition in that department.
Although at its core, it's essentially the same software, namely iOS, each variation, such as watchOS, tvOS, iPadOS, features exclusive tweaks to support the device they're meant for. Most noticeably, they have minor or major interface differences, with a lot more changes in the background.
The firmware change may also be meant to adopt new functionality that could be present on a future device. Apple is reportedly going to release a cheaper, smaller HomePod later in 2020, in an attempt to compete with Amazon and Google more directly.
The Cupertino company is also working towards including additional music services, with Apple Music initially being exclusive to the HomePod. Siri improvements are also expected, with a focus on increasing its smart home functionality.
Earlier this year, Apple quietly acquired an AI firm that specializes in on-device AI technology, meaning that machine learning and image recognition features, among others, can be feasible without the need for connecting to the internet. We're yet to see whether that move was made in an effort to improve Siri across all devices, including HomePod.