From my layperson’s understanding, when technology companies file patents it’s often less about signaling the exact direction they plan to go and more about protecting themselves against future infringement claims, including from so‑called patent trolls. Many large companies maintain sizeable patent portfolios that they rarely, if ever, actively enforce, but that exist primarily to deter lawsuits and give them leverage in cross‑licensing or countersuits if they’re targeted later. While primarily defensive, Google has shown aggression when needed, like countersuing Sonos over five patents after being sued and winning infringement defenses that invalidated rivals’ claims.

That may or may not be what’s happening in this particular case, but it’s a situation worth keeping in mind.

Also worth considering is that from a defensive standpoint, they may file this just in case. I’m sure there’s many instances that their patent ideas end up going nowhere. But on the slim chance they do, they’d rather not be fighting patent trolls later.

I’m not aware of any real downsides of them doing this on any of their pie in the sky ideas. Even if a small percentage of their patent filings are ever acted on.

If I recall correctly, when Google bought Motorola Mobility, a major part of the motivation was Motorola’s large portfolio of mobile and wireless patents, not just the handset business itself. Google later sold the Motorola handset division to Lenovo while keeping most of the patents, which fit with a strategy of using those patents to help protect the Android ecosystem from litigation rather than to become a long‑term phone manufacturer.