If they can survive the cuts then I definitely have hope. I liked Dart enough to be happy with using it; I like the Flutter ecosystem in general as well. It'll be interesting times in app development if they can make a better cross-platform solution than currently exists.
The HTML renderer is actually what was first, canvas came later. The canvas is the first class implementation while the HTML one is a fallback for mobile performance and I assume if canvas is fast enough, HTML will be dropped as well.
It can often be a lot slower and laggier than the mobile and desktop experiences, for whatever reason. However they are working on improving it with WASM, Impeller (a new renderer which should be faster by being more suitable for Flutter specifically instead of Skia which was more general purpose), and so on.