DataDrake Thank you for your reply.
It's important to realize that it's all about perspective as well.
I agree with that. Our personal experiences concerning the Xfce desktop and especially its stability seem to differ. I have been using the Xfce desktop for years on different distributions, previously on Mint and currently on Void and Gentoo, and never experienced any issues. I have tried out other desktops like MATE, Cinnamon or Plasma, but always found myself going back to Xfce after a short time. I enjoy its simplicity, responsiveness and stability.
On my mostly short intermezzos with the MATE desktop I experienced several issues/annoyances. On my laptop the keyboard backlight gets turned on every time I log in. This only happens with MATE (I know how to work around this issue). Another issue was, that my panel applications got rearranged every time the screen resolution changed (I didn't forget to lock them). That issue occurred with another installation I had several years ago (not Solus). I don't know if it happens on Solus because I haven't changed the screen resolution since I installed it. So in my experience MATE has been buggier than Xfce.
I absolutely agree with what you said about the more than 4 years it took for Xfce 4.14 to be released. And it was mainly a porting only release. So that certainly shed no good light on their development activity. I hope they will be able to regain some of the credit they lost in the future.
I would also point out that your earlier criticism about Marco not being replaceable isn't true. You can swap it with Compiz.
I didn't say that. I just stated that because of Xfce's modular approach it is possible to replace Xfwm or its compositor with Compiz, compton or whatever else. That doesn't imply any criticism concerning MATE. I'm well aware that MATE Tweak tool allows you to switch between Marco and Compiz as composite manager.