All the different distros are all about the vibe and not a lot else. The Linux kernel remains pretty much the same and we just choose different window dressings.
I suppose we could role it all back to Debian Stable and Slackware I guess. Do we need a "Distro Thanos?" Besides, without all those different distros, how you gonna surf?
After doing a quick search, I don't see enough differences for the Zen kernel to claim it's so special. The main line kernel has to be a "one size fits all" from servers to gaming and anything in between. Zen is just a recompiled mainline kernel with some chosen optimizations for better specific use cases-- mostly desktop/gaming. Which is nothing I can't do if I recompile my bog standard Fedora kernel for those optimizations.