Your own links show that likely isn't parent's issue. It only sends a hash on the first run of an executable. I'm not saying the problem you're talking about isn't a problem or concerning, but it's very likely not the problem they're talking about.

I hate when people say "mine works," but here's an `ls` of my homedir showing it's not universally slow. I currently have an absolute garbage network connection.

> ls -G 0.00s user 0.00s system 64% cpu 0.010 total

There are also many, many other reasons it could be; some macOS specific and others that aren't--most importantly what they're seeing isn't universal. macOS often ships with very old GPL2 tools that can cause various problems (many people brew install updated GPL3 versions), people often have configurations that can slow down `ls` by multiple factors (colors, sorting, etc can each cause multiple queries to disk or require the listing to complete before displaying output), customizations causing a slow prompt, a slow or corrupt disk, listing a slow network drive, etc.

The VPN bypass was very quickly removed from macOS over a year ago [1]. So it would only be relevant if they were using a very old version of Big Sur.

[1] https://www.patreon.com/posts/46179028