Unwarranted fear.
There is a perception of Linux as this hacker, terminal-only OS with a million equal choices and no direction or guides. This is not a true view or at least this is hyperbolic/based on Linux from 15 years ago. It is a stigma that Linux has. Every distro these days has to market itself as "We're the out-of-the-box distro" which is just silly. Out-of-the-box is meaningless. Even Windows users modify their OS in certain ways. However, it breaks the stigma.
Linux adoption just needs more time. Most of the big issues for adoption have been solved in the past few years, and Linux is ready and knowledge of Linux and removal of the stigma is growing.
The problem with that is most major distros market themselves as "new user" distros to some extent though. Noob-friendly, out-of-the-box, easy, etc are all distro-marketing buzz-words that mean nothing.
You can't expect them to only use Wayland, Pipewire, Systemd, and Flatpaks because that dream requires every distro to use Wayland, Pipewire, Systemd, and Flatpaks, which will never be reality.
Most distros will probably eventually adopt these tools, but there won't be a sudden shift. It will be gradual.