I think we live in a time period where seizing/searching phones doesn't need the physical device to be present. They just have to ask Google and Meta to do it for them. Different than literally combing through the memory on the device, but not much. It's why FOSS and selfhosting matters so much. What Google and Meta don't have, they can't just take.
That being said I would bring a burner if I went to the US. Lord knows I have said more than my fair share of critical things about the US government lol