Reading thru that C&D You have a win(win?). It says that You "Have stopped and will not in the future access the Facebook and Instagram websites and/or use Facebook’s and Instagram’s services for any reason whatsoever;". As soon as You get on any page where there is the famous Facebook pixel, (like cloudflare.com) You have accessed a Facebook Ad services without Your knowledge. So essentially they wanna ban You from the internet (which they cannot IMHO) or they will have to delete Your data from their database in compliance with their C&D. I'm pretty sure this can be elevated as something pretty ridiculous and maybe there will be a lawyer keen enough to protect You and kick FB in the ass for this.