Method 2 seems very straight forward, and I've worked with SIP before (so I know how careful and exacting I have to be).
An alternative that doesn't require you to navigate anywhere in Terminal is to type sudo rm with a space typed after rm. Don't press Enter yet. Drag a font you want removed into Terminal. Its path and name will be appended. Now press Enter. Repeat for each font you want to remove.
You can also use wildcards this way. Using the NotoSans fonts again as an example, after dragging one of the NotoSans
fonts into Terminal, use the backspace/delete key to edit the full font name down to NotoSa, type an asterisk *, and then press Enter.
8. Continue removing fonts from the Fonts and Supplemental folders. Close Terminal when done.
9. Restart into Recovery Mode. Re-enable SIP in Terminal by entering: csrutil enable
Type reboot to return to the normal desktop.
Where are the fonts listed so that I can drag them into oblivion?
Much thanx, Michael