Agree with you. Neither have I. My 'gut' must be totally dead. I never have any sort of instinct, I'm just streetwise, use my brain and follow any sensible safety precautions. I'm not denying it exists, but I'm sceptical. And I don't have it. I can see when things are about to kick off, or when someone is suspicious, but it's fairly obvious and not any sort of mysterious instinct.
My mother always claimed to be almost 'psychic'. A very good judge of character, etc. according to her. Until one day (and she told me the story herself) she was at a restaurant, alone. And a man asked to join her. They were chatting and both liked each other. Mother said, the man was her age, good looking, well-dressed, smelled nice, intelligent, good sense of humour, they just clicked. She really fancied him and agreed to meet him him again, as she had to go to an important meeting and couldn't stay.
Well what do you know. The dude turned out to be an absolute criminal, in an out of prison for various things. Rape, drugs, beating up his ex partner viciously. So much for the 'gut feeling'. They didn't meet again, but not because of the lack of trying. He couldn't come. Because he was arrested at the time.
As for the OPs example, yea. If the perp is that dude from twitter David Atherton, then I'm not surprised multiple people had 'gut instincts' about him. He's very obviously one sandwich short of picnic. And then I wonder. Take Chris Watts. A conventionally good looking, friendly appearance, smiley, mild-mannered, seemingly absolutely nice and normal man (from pics and videos). No one suspected (afaik) he'd do what he did. Another even more famous one. Ted Bundy - also a good looking (for argument's sake, it seems to be agreed and he's referred so), charming man. Multiple victims trusted him, went with him, wanted to help him. Would they want to help/go with/sit in a car/chat with David Atherton?