@mgubi thank you for sharing your points with which I mostly agree, in particular :
Just to clarify, I don’t think using markdown to generate pdf is interesting, Texmacs already does that very well. The idea is not to use a crazy and unproductive workflow.
An export to a “gateway”/generic format is reassuring for new users, powerful for confirmed ones. Pandoc seems to be one of the best placed candidates indeed.
Where I may have been wrong is how much energy and willpower Texmacs developers could devote to developing Quarto equivalent features in Texmacs. This is why a quality export to markdown seemed relevant to me.
The idea of supporting an export to a “gateway” format is also to avoid having to reinvent everything, but I understand very well the idea of wanting to do it in Texmacs, it is indeed strategically the best way to attract the most people.