age or actions?

This is a question. This is not my situation. I am genuinely curious to hear your experiences and maybe your age difference if this post applies to you.
I am curious how much age plays a factor if the emotional and spiritual connect is there between two people. Assuming everyone is of legal age 18+, how much of an age difference is okay? I am mostly curious about men or women who have dated younger than themselves. Can anyone give some input on their experiences or views? Thank you!