This seems like lets make TW more like Notion. But I think that that space is already occupied… well by Notion and its closer clones.
While I would like to have more compatibility with Markdown in the form of exporters/importers, I don’t think that Markdown can replace WikiText because of the extensibility of the last one. Also regarding paid plans, there are starting attempts, like the ones discussed on Paid plans for TiddlyHost.
I think that the steering committee should be more like a non-profit umbrella that maps/connects different alternatives to keep TW extensible and make it more sustainable in the future, which is not incompatible with some calls to make TW more “enterprise ready”, but that could be done by the professional associations and enterprises around TW. A model that comes to mind regarding bridging community, professional, academic, enterprise initiatives around a technology, without the particular agenda of one of them above the others, is the one of Pharo. Of course, others are available also, but this is one I’m familiar with.