You realize that that “rule” is based on absolutely nothing, right? It’s just arbitrary nonsense that people who are terrified of disorder impose on themselves because rules give them a pleasant secure feeling even when the rule ridiculous :-D
‘creepy’ is a feeling. and like all feelings it is entirely in the eye of the beholder. ‘predatory’ is stupid fear-mongering bullshit. Certain TV personalities made tons of money scaring the fuck out of parents, and they did it by using the vivid violent imagery of vacuous metaphors like ‘predator’
People in their 20s are perfectly capable adults. They are not harmed by consensual sex with people older than them. There is not a shred of evidence that folks over 30 are somehow dangerous or have magic brainwashing powers that they use for evil :-D
So, yes, it’s all in your head. Your culture has taught you to fear something that is 100% harmless on every level.