Please don't take the, in my opinion, excessive criticism to heart. Mermaid is fantastic. It would be even better if it supported more renderers but as it stands to day its an invaluable tool.
That I can bring GraphViz into a browser but not Mermaid out of the browser forces GraphViz for some usecases. Unless browser-native was the intent (idk, it could be... maybe thats why it was named Mermaid), I do think it should be a high priority thing.