This is confusing. If you end it then you will never know if it could have been more. If you remain friends then you risk always being friends with benefits. I would be friends without benefits. He has no reason to reach for a relationship if there is sexual activity. I think friends with benefits sets up a possibility for no commitment. See what happens if you just keep the friendship going. He may realize that you have shared interest and compatibility. I don't think the age difference is that big. I think he thinks it is. At the very least, you have a good friend.
If this has been helpful press accept. Sorry for the delay