Apple Breaks Basic Functionality in macOS Crapalina: Terminal.app Cannot Access Files Even with Full Disk Access and 'sudo'
You have to wonder who thought up the security in macOS Crapalina: using Terminal.app, I have trouble accessing my own files (“permission denied”). Seriously?!!! Yeah—files for which I am the owner with read and write permission. I rely heavily on Terminal, and this was very confusing at first, since it would work with some files in some places, but not others.

What kind of sense does this scattershot behavior make? The macOS Crapalina security scheme is tied to the GUI infrastructure in devious and unpredictable and flat-out idiotic ways which confuses the issue even more. It is disturbing in its erratic behavior, especially for a system that is Unix at its core.
Most users will be utterly baffled and dismayed if they ever do anything even slightly out of the ordinary, and will quickly be trained to dispense with the nuisance dialogs (“foobar.app wants to access the stuff you’ve allowed for 57 other apps, is that OK?”) , making the whole scheme (an appropriate term) lose most of its security value.
The security in macOS Crapalina is a steaming fly-buzzed pile of security theater that users will quickly shovel away to get work done. But shoveling this shitpile still doesn’t get the job done.
How to make Terminal work more often
Anyway, to make Terminal work properly, give it in How to Add File/Folder Access Permissions in macOS Catalina. It should look like this, below.
Except... that it still won’t work, even with sudo on top of this... see below.
NOTE: changes might not take effect until the padlock icon is closed or the window is closed. You must also close and re-open the application(s) for which permission was added.

Still does not work
Problem is, even giving Full Disk Access does NOT really allow access, not even using 'sudo' as can be seen directly below.
The broken design of Apple’s latest security infrastructure can be seen in the screen capture below: even given Terminal.app is unable to even list most of the applications in /Applications/Utilities. And that is hardly the only place this problem occurs.
and using 'sudo',My own software will run but won’t install into /usr/local/bin. The incoherence of that should be self-evident to any used to unix.
Apple is seemingly hell-bent on destructive design incompetence in macOS. This is so ridiculous and so unacceptable as to merit some kind of Jackass Design award—any artists out there (?)—I need a graphic going forward, because it might just get worse.
