I’ve long had the stance that mermaids killer feature is that GitHub supports it natively. Ultimately for engineers having rendering at the place where they do the vast majority of their work is huge.

The actual drawing engine sucks compared to something like Graphviz. Works fine up until a certain number of nodes but completely falls apart after that

Render an image and put it in the repo, in this way github supports all sorts of tools.

Do you want to risk that your diagram changes outside of your control? (i.e. GitHub changes a mermaid version)

Yes that's essentially my thoughts though perhaps a later feature would be to support the tool customizing d2 files as well! I also think another part about starting with supporting mermaid syntax is that the AI coding agents seem to emphasize mermaid in particular [1] so if they are writing in that syntax anyways I feel it will be even more the norm.

[1] https://cursor.com/docs/configuration/tools/mermaid-diagrams