I had the same hope the last time this clown was president (welp, there goes my US visa). It didn't happen. Maybe this time it'll be different but as long as conservatives have any saying in EU politics I'm very much sceptical.
No, you need to buy your own ticket like the French scientist had to. The flight back isn't free either unless they insured the travel for such conditions.
Wow. What happened to the love for the constitution?
AFAIK the constitution doesn't apply here. I can't remember who or even when it was but there was a musician or actor who once said in a TV interview that they consumed pot in the past and then were turned back to where they came. See also https://www.usentrywaiverlaw.ca/marijuana-tourism.php
Basically: The US has been hostile not only to migrants but mere tourists since quite some time (at the very least since 9/11), even under Democratic administration. On entry, don't admit to anything and wipe your phone (restore a cloud backup after successful entry). Or even better, don't go to that shithole country that treats people who fund the tourism industry like criminals. If they don't treat you like they want your tourist money, they shouldn't get that money in the first place.
I want to know how they got access to his phone. Did he hand it over willingly? Did they run some kind of scan by connecting it to a device? Did they have a court order or authority to search it?
How do we help others avoid this sort of thing? My recommendation: start using Signal.
It was there since a long time. People coming to US are warned by foreign organizations about the port checking the contents of their phone, text, photos, apps etc. It just didn't happen as often as it does now.