What is this tag filtering feature called and why do so few apps have it?

1

TiddlyWiki

You can do this fairly easily with a macro in Tiddlywiki. There are even “versions” of Tiddlywiki that behave like Roam that are free if you like that format.

#Note Taking #Knowledge Base #Personal Knowledge Base 180 social mentions

You can do this fairly easily with a macro in Tiddlywiki. There are even “versions” of Tiddlywiki that behave like Roam that are free if you like that format.

#Note Taking #Knowledge Management #Knowledge Base 8 social mentions