The majority of the community feels this way which says something. The author's reaction is to publicly display being upset and dismissive of the communities reaction. That is just making it worse.
When you work on a project this big, more care is needed. The commit was an innocent mistake. The blunder is blowing off the communities response as overblown which it would be had the commit been tagged experimental. But it wasn't. And the author did themselves no favor blowing it off.
If the author was smart, their reply would simply have been:
Hello, To clarify, this is an experimental branch only. There are no plans to port, only experiment. I will tag the repo as such to ensure people understand its intention and avoid future misunderstandings.
Nothing difficult to understand here.