Re: Who cares?
They cannot comply because the US insists any citizen, corporation or entity of any kind that trades in or with the US is covered by US law, that US citizens are always caught by it wherever they are. If 'billion dollar' US companies do the only remotely plausible thing and separate into legally different EU and US companies with no US citizens abroad they'll still struggle to cut enough perceived ties to stop the US continuing to harass them.
The US doesn't believe anyone is safe from their justice. Most of the rest of us don't believe their justice is fair or proportionate enough.