What is an Apple-SCC file?

It is an Apple Support screen sharing app. It must be left over from some old Apple support session you had at one time.

.... this makes the point that erasing the hard drive does not necessarily give a "fresh" install.

Erasing the hard disk leaves it completely empty. Nothing remains.

As long as Time Machine is subsequently used to put Apps/Files back, then whatever garbage was there before, associated with Apps (even deleted ones), just gets reinstalled.

Correct.

This is one reason Apple doesn't use the terminology "fresh install". At best it's misleading.

• If you want to erase, erase. Nothing remains. You're done.
• If then you subsequently want to reinstall, proceed with reinstalling macOS, optionally followed by migrating selected Time Machine files — an option the macOS installer suggests upon completion . If you do not migrate or restore those files, your Mac is essentially left in its original "out of the box" state.
• If you want to restore a Time Machine backup, for example after messing up your system for whatever reason that may have occurred, then select a TM backup and restore it. However, that does not require erasing the Mac or reinstalling macOS as an initial step.

In your case you appear to have restored a TM backup containing those files. It worked exactly as it should. Since you don't need them, just drag them to the Trash (along with anything else you don't need).

Did you restore from your backup? That would restore those files.