[saulpw]

(Author of VisiData here)

I don't know what the issue is on your computer, but it definitely doesn't take my computer 500ms to register a key press in VisiData in the general case. That would be an issue I'd have to take seriously. I've spent way too much time optimizing VisiData's startup time to be under 300ms to let something like that slide. It's a point of pride for me that VisiData doesn't incorporate that "web GUI bloat" as you mention.

If you're willing to help out, please contact me so we can file an informative issue and see if we can figure out what's going on in your setup. I have a hunch it's generalized computer/OS bloat that we (VisiData) can't do anything about, but at least we can try to understand it so that hand-crafted software like VisiData isn't unnecessarily maligned.