It really isn’t all that popular these days
It's popular amongst regular linux users, I mean if I was to take your opinion seriously then someone clearly made a mistake here:
https://survey.stackoverflow.co/2024/technology#1-operating-system
Someone put Ubuntu in 3rd (after Mac and Windows) and Fedora in 12th under ipadOS and "Other linux based" 🧐
In terms of popularity amongst neckbeards who argue over linux distros then yeah, Ubuntu isn't that popular you're right