Won’t cost them anything near weeks of dev time. They can just write it into their terms of service and prompt you to re-accept those next time you access the site.
You can’t bypass laws, but the law in question only requires permission of the enduser. Getting this permission in your ToS isn’t bypassing anything, it’s acting according to the law.
that’s not true in the EU.
the reason those cookie banners are everywhere, for example, is because the EU requires explicit consent for a lot of things that used to be covered by ToS.
simply putting clauses into your ToS doesn’t shield the company from legal action at all.
regardless of what’s written in the ToS, final say over what is and isn’t legal lies with local authorities, not YouTube.