US v. Cano: "we hold that manual searches of cell phones at the border are reasonable without individualized suspicion, whereas the forensic examination of a cell phone requires a showing of reasonable suspicion". Neither "without individualized suspicion" nor "a showing of reasonable suspicion" are a warrant requirement. This is not a court "ruling against warantless border searches".

US v Aigbekaen is an individualized suspicion requirement, not a warrant requirement: "individualized suspicion of an offense that bears some nexus to the border search exception’s purposes of protecting national security, collecting duties, blocking the entry of unwanted persons, or disrupting efforts to export or import contraband."

I think another problem is that such suspicion/probable cause is often "made up", or in other words, people often disagree on someone's quick judgement call where it wasn't obvious to everyone.

Yeah. This wasn’t even an appeals court, so all this means is this judge thinks that.

As it is I wouldn’t be surprised if the government doesn’t appeal to avoid setting a wider precedent.