If I was desperate for kudos I would not be out here posting villain ships, minor character rarepairs, and other deeply unpopular ships.
I know how to write popular fic. I know how to farm kudos. That's not what I'm here for.
"Readers need to remember that authors don't know a reader liked their fic unless the reader tells them by leaving a kudos or a comment" does not mean "waahhh waahhh I need attention!"
It means "even if writers write purely for themselves, if you don't bother to interact with writers when you do enjoy their work, they might stop posting and just keep their work to themselves."
"If you enjoy a work you should kudos or comment" is not aimed at the people who aren't reading the fanfiction in question.
"If you enjoy a work you should kudos or comment" is not aimed at the people who did not enjoy the fanfiction in question.
"If you enjoy a work you should kudos or comment" is aimed at people who read a fanfiction, enjoyed it, and then didn't bother to even do the bare minimum to share their excitement about it with the work's creator, even though that excitement is literally the only thing they get in return for posting their work.
Fanfiction authors write because they enjoy writing. They post because they want to form a connection with the people who enjoyed their work.
This is not an attempt to scold anyone, I literally don't care if I get kudos or not. It's simply an attempt to remind people that fanfiction is a community, and fan authors can't read your mind.