I suppose the relative lack of interest comes from vector tiles not being a format in which anyone actually stores their data. Vector tiles are an intermediate format into which you can preprocess a big data set so that this big data set can then be rendered with an acceptable speed, typically by a web client.
With Manifold, you don't need vector tiles to render big vector data sets with an acceptable speed. We have Manifold Server that does this, and it does this via different means. Manifold Server does not currently support web clients directly, but it will in the future, and we won't need vector tiles to do that well. That said, for web clients that already support vector tiles, we might allow generating them on the server, too. In that case, vector tiles won't be something you will have to deal with (generate / move to the server / periodically update, etc) directly. If we do everything right, you will simply tell the server "btw, I would like you to generate vector tiles" via setting an option and it will just do that automatically.