The good thing I'll say is that somewhere around 57 million people visited the US last year. 99.9%+ had no trouble other than long lines and the general frustration that comes with long distance travel. So your fears, while completely understandable, are also very, very unlikely to cause any actual trouble.
We get it, people who comment on sweet puppy Instagram posts aren't under threat. Sure. But the IT folk, especially people having access to sensitive information or white/black hats can definitely expect a plethora of insolent questions at the airport, asked in small creepy rooms somewhere at the back, from people who refuse to even identify themselves. Is that even legal?
Shall we also mention the looming danger of own laptops being banned on flights? Either use a Chromebook-like device (which, I have no doubt, will steal your private data, why else would they setup such a honeypot anyway) or GTFO, that's USA's policy.
I've made up my mind. I am not going to the USA for now. There's undoubtedly a huge pool of interesting people who can make some of my business dreams come true there but I am not sure being recorded in an unofficial "special target" list for life and having my devices every time I go confiscated is worth it. I'd say no.
(I exaggerate a bit of course, but to the average guy like myself losing even a $250 throwaway device is something that I will feel.)
So he probably was on some kind of a radar. Are you? Then you concern is completely warranted. Are not? Then it's not.
Like, at levels only seen in 1 out of every 100,000 visitors, making it quite likely you'll be one of the 0.1-% percent if you hold these extreme viewpoints?