I don't think anyone here can answer your question. But I think that it's unlikely.

The majority of blind Android users are in developing countries with limited access to braille displays, so improving it would not have a large return on investment. Improving BrailleBack would also not attract users from developed countries because it is well-known that Google is much slower with accessibility than Apple and Microsoft, and Google's unwillingness to add new features to TalkBack is a clear indication that, in contrast to VoiceOver, there would not be continued improvements to BrailleBack in the long term.

The reason that they have improved braille access to things like GSuite and Chrome OS is because they know that if they don't, they will suffer financially because of the obligation of some businesses, schools and government departments to procure accessible technology; by contrast, very few businesses mandate that their employees must use Android, so they have no legal or financial pressure to improve Android accessibility.

Don't count on it. TalkBack didn't become properly usable until Android Nougat and it's gotten mostly bug fixes since then. No reason to think they would give more attention to the much less popular Brailleback.

No.