The day after TSA failed spectacularly in reviews that made it to national news, I missed a flight because they thought my portable hard drive could be explosive. The guy who inspected it? An "expert" over Facetime because he was at the Arnold body building conference. Then they GAVE IT BACK TO ME and told me I had to ship it. What a joke.
Scanners have gotten better recently, meaning they can tell the difference between water and explosives, but these restrictions weren’t pulled out of thin air like many others.
That doesn't mean it's not still a show. In the 2010s (forget when exactly) the TSA was tested with fake bombs and let them through 49/50 times. They have never successfully stopped a terrorist attack either afaik.