I think the complaining is 10% real concerns and 90% people upset that it is different than it used to be.
Also, people love change if you have actual improvement. I was very happy to switch from sysvinit to runit.
Wayland does specify only two thing: how to exchange buffers between applications, and agree on protocol extensions.
Then, you can make the inner workings as many pieces as you want. The "no window manager" is a fallacy. You could decide to write a compositor that offers a protocol to manage the windows. I'm pretty sure you can more or less do that today if you use sway.
The one thing Wayland doesn't do is specify the 1000s of things X11 was doing, most of which are hacks upon hacks on interfaces that were not designed for the stuff people are doing with.
But it isn't. Have you ever tried to use X11 without any window manager? You can't! In the best case you can type inside a terminal that is not moveable or resizable. X11 can not function on its own, hence it can't be monolithic.
Just because it is bloated doesn't mean it is monolithic. And most of the bloat is old graphics drivers which are not installed on your system anyways.
I'm not really liking X11 either. Just like I switched from sysvinit to runit I would be happy to switch from X11 to the next best thing. But Wayland is not it.
The protocol is flawed on so many levels but most importantly because it does not provide the necessary interfaces required for normal, functional desktop and degrades them to "implementation details" (or in your words "1000s of things"). Just blitting bitmaps is not sufficient for a working desktop system. The biggest pain point is access control policy, which Wayland completely ignores.
Wayland on the other hand, it really does need to do everything well. If Zoom won't run in Wayland, needing to launch X11 to run Zoom means Wayland is broken.