Cybersecurity engineers and pentesters don't need Kali or Parrot. You don't need Proxmox to use LXC and KVM. You don't need OpenMediaVault to have Samba and NFS shares. You don't need Clonezilla to make use of the OCS toolkit. You don't need LMDE to have a Debian OS with Cinnamon and nonfree drivers installed, or Endeavour to have Arch with KDE Plasma.
But it's sure as shit good to have everything packed together and preconfigured by professionals.
I mean, bait aside, creating a new distro with an existing package manager allows you to set up a different set of default packages and even add your own new/updated ones. That's the value of it there.
New distros get a lot of crap, but often they are solving a need for someone.
Take Windowmaker Live: ostensibly it's just Debian + Windowmaker. I have seen comments saying why not just install WM on Debian? By asking that question, it's clear the asker hasnt tried recently. There is a lot to configure, and there are lots of usability papercuts.
A custom distro allows someone to fix those problems for themself, and share those fixes with others. It's not fragmentation, it's just FOSS.
I'd say actually a bit of the opposite. Generally speaking we don't need a new package manager or init system, and better hardware support is almost entirely a kernel concern (one might make an argument that the loose bits of key management and tpm2 tools and authentication agents could be better integrated for "Windows Hello" type function I suppose, but I doubt that's what the meme had in mind.
Not really needing to reinvent the wheel on those, we got a variety of wheels, sometimes serving different sensibilities, sometimes any difference in capability went away long ago (rpm/dnf v. deb/apt).
The best motivation I can think of at this point is to make specialty distribution that is 'canned' toward a specific use case. Even then it's probably best to be an existing distribution under the covers. I think Proxmox is a good example, it's just Debian but installer made to just do Proxmox. You want to do automated installation? Just use Debian and then add Proxmox (the official recommendation), because they have no particular insight on automated deployment, so why not just defer to an existing facility?
The biggest conceptual change in packaging has been "waste as much disk as you like duplicating dependencies to avoid conflicting dependencies", maybe with "use namespace and cgroup isolation to better control app interactions" and we have snap, flatpak, appimage, and nix very well covering the gamut for that concept.
For init, we have the easy to modify sysv init, or the more capable but more inscrutable systemd. I don't see a whole lot of opportunity between those two sorts of options already.
Every project eventually makes their own package manager. Its pretty insane if you stop and think about how routinely the package manager is re-invented.
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?
So it is basically just like choosing which app to access reddit with, except that if i choose the wrong app i might be auto-banned from a lot of the subs?
Also, i won't see stuff i am searching for sometimes, because the distros sometimes make trouble if someone else hasn't already subscribed? Or is that only on mastodon?
I am using Voyager, and chose lemm.ee for no apparent reason. But so far, it just feels like a shittier version of reddit but with better mods? I dunno.