I used to think that, too. But even Ubuntu and Debian are very different operating systems now.
On the other hand, it’s all Linux under the hood, and almost all computing tasks can be done on almost any distro.
Finally, almost all distros exist because people choose to maintain them as a hobby without payment.
Who am I to judge whether they should pool their resources on fewer distros in their free time?
I drink and doomscroll in mine.