I disagree. These legal visa holders are caught for small (or slightly larger) infractions, like a previous visa revocation due to running a cannabis business, sort of working (helping?) on a non-work visa, obviously planning to work on a non-work visa, etc. These could always (at least after 911?) land you in big trouble in the U.S. if you have the wrong nationality and/or skin color. I believe these were almost completely ignored by (mainstream) press because most Americans won't sympathize with them, they are obviously illegals, criminals, terrorists, etc. Now that Canadians/Western Europeans are caught in the system, suddenly people with the same infractions or suspected infractions are obviously legal visa holders.

I personally know someone with the wrong nationality and wrong color who was detained at the border (maybe not technically "detained"? let's say held) for no apparent reason for hours and got their devices searched, then released and allowed to enter. That was either 2013 or 2014. Thankfully not weeks or months.

The only fundamental change now is the bar is lowered and sympathizable (to most Westerners) people are being caught in it.

And I maintain that people who actually valued inclusion shouldn't have held conferences in the U.S. since a long time ago, if ever.

The agencies don’t reveal reasons why someone was denied or detained, so there is no evidence whatsoever that someone was detained for being critical of Trump. The claim that this happened is from Philippe Baptiste, a French minister for higher education who has been attacking America continuously in a bid to attract researchers from the US.