magic is too dangerous to be left uncontroled. Kinda like explosives, or simply handguns. Useful for civil uses, but no government in the world will be happy if you just run around using that kinda stuff for your own interests, without any form of license and register. That's not totalitarian, that's sensible. IRIS can not keep the anti-magic shields secret from humanity (and not expect a massive backlash for trying to do so). The anti-magic shield with the whitelist system is convenient, and seemingly a perfect solution. If your magic is harmless, just get some sort of magic license, like a drivers license, which includes some very basic psychological evaluation, and tests that you have your magic under controle - yes, magic people could kill thousands even without being evil madmen, just look at Alice and her curse. If you are harmless, bam, whitelisted, enjoy your magic. If your magic is primarily explosions and death, you have no business using that kinda stuff unregulated in a major city
it's not discrimination, it's that if you can't controle and/or your emotions, magic users may be a danger to themselves and others.
it's also about equality. mind-readers or mind-controlers, super speedy people or people like Will, there is no such thing as a fair competition against people like this. It's not like mages have to live in ghettos because they are dirty and blah, and if they have to, then certainly not in all countries. France seems like a place where that would not happen, that's more china or russia style. All that is asked is that if you can cause and earthquake, the government would like to know that, and if you cause one without permission, your ass is grass. That's how law works. Replace the word magic with gun and bam - there will be tons of people who will tell you that the above laws are not nearly strict enough. And magic can be way more dangerous than guns. Remember the dude who teleported air into a tight spot so it underwent nuclear fission