Web page can run (and some code-focused pages do) code folding code, so the question is still relevant with minor modification.

The whole premise of losing productivity and spending time in the most common case to support underpowered rare use cases is deeply flawed.

It's similar to the argument for using bad defaults in config/keybinds 99% of the time just because in 1% of the time you would use another computer without your customizations.