In theory, acting on attraction is a bigger deal than simply possessing it.
If you're attracted to someone who's vulnerable, someone you have a power differential over, a minor, someone with significant developmental or cognitive issues, someone experiencing a mental health crisis, etc, you owe it to both yourself and to them to not become involved in that sort of way.
If one believes their affection for that person is sincere they should be willing to recognize the need to place the other party's well-being ahead of their own desires.
But broadly speaking, no, there's nothing wrong with being in your 30s and pursuing a 20-something so long as none of the previous is applicable to that person.
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The Party told you to reject the evidence of your eyes and ears. It was their final, most essential command.
If you're not careful, the newspapers will have you hating the people who are being oppressed, and loving the people who are doing the oppressing. —Malcolm X
Make America Great (Depression) Again