People saying Rudeus should only be with someone older because he was in his 40s when he reincarnated... Wouldnt you be complaining if the 13 year old Rudy was being pursued by 40 year old women??
Hows he gonna explain that?? Imagine a child coming up to you and saying "Milady you must understand, I was a middle aged man in my past life!!"
So what? He can't find love? Even the one person he knows of who got isekai'd with him is still 16 as far as I know.
Who cares. Its fiction
Like the mental gymnastics is insane. Just enjoy the media or ignore it and let those who do be in peace