Bad news? VSCode supports WYSIWYG editing (e.g., see "markless" plugin)

See: https://github.com/tejasvi/markless

And the note taking app “Dendron” will be implementing something similar to provide WYSIWYG note taking in VSCode. See:
https://news.ycombinator.com/item?id=29176158#29178184

WYSIWYG is not the only feature of texmacs.

AucTex and Lyx can do WYSIWYG for many years

But it would be nice to see TeXmacs support WYSIWYG note taking… more people might use it.

What do you mean by that? I would think that’s exactly what TeXmacs does.

I don’t get what so new about the programs you link. It seems like you still have to edit LaTeX in source mode and this just gives you a live preview and/or displays the result when you’re done editing. That’s nowhere near TeXmacs’ live typesetting and editing directly in the typeset equation.

Besides, as @slbtty already said, there’s much more about TeXmacs than wysiwyg; there’s the macro system, its interface to various plugins, its extensibility through Scheme, its convenient keyboard shortcuts, structural editing, beamer mode, graphics editing, …

Today’s more advanced note taking apps focus on ways to help you organize and find information.

I mainly see ways of constructing trees or graphs of pieces of information, graphically representing and browsing them. Many of the necessary ingredients are already present in TeXmacs, so it can probably be implemented.

In addition, I find the title inappropriate. If there are alternatives, that is OK and normal. Why would you call it “bad news”? The developers of TeXmacs does not think of monopoly, unlike Microsoft.