I had to read this several times.
One of the great things about Protonmail is unlike Whatsapp, they can’t read your messages.
What they did was under court order, gave police the IP address of the offender.
The police then tracked them down using the persons ISP.
They did NOT give them email transcripts as they have zero access to them.
Yep... Even the FR would be forced to do the same in this case. In fact every domain in the country would also have to do the same in this legal situation. It is federal law.
A good VPN is pretty much a necessity for any online activity these days.