Is it 100% confirmed? No, but that's part of the brand trust referenced in the original post: where there's smoke, there is probably fire, and it would be beneficial to brand trust if Google provided a longer-term roadmap for these products.
Before someone comments "Why doesn't Apple need that type of roadmap?": because Apple has the hardware brand trust that, say, the iPhone isn't going to go away next year simply because the engineers working on it wanted to create an iMessage competitor.
[1] https://www.bizjournals.com/sanjose/news/2019/03/13/google-h...