I don't understand why my mod "isn't popular enough"

Dear aternos support. I am currently making a mod for an SMP. Here is the link: https://www.curseforge.com/minecraft/mc-mods/elemental-races

This mod already has over 5k downloads. But when I try to suggest the mode in the field, i get "this mod isn't popular enough", then i saw that some mod only has 3k downloads and is approved on aternos? I really dont understand what should I do, cuz i really want to start an SMP with this mod this summer, and I cant even get it approved on Aternos .

Then can you give at least some numbers? I want my mod to be on Aternos, and I dont know what I need for it.

Also what popularity is then? Because I have no idea what to do and how to advertise my project.