Ok you seem to be right that there is an issue here for the closed source graphics drivers
quoting from https://wiki.ubuntu.com/Wayland:

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"Will video drivers need to be rewritten for Wayland?

No. Most of the open source drivers have been undergoing rewrites in recent years to support KMS, GEM, and other modern graphics technologies which move more of the graphical functionality into the Linux kernel. Wayland leverages (and requires) these technologies; indeed the whole reason Wayland can exist is because of these changes. But those changes were underway for X in general. In the future Wayland and X will both be using the same graphics drivers.

What about the graphics drivers still in X?

Graphics drivers such as Intel, Nouveau, and Radeon include both kernel drivers and an X driver. With Wayland we only need the kernel drivers. Under the KMS/DRM/GEM architecture, that's where most of the real functionality is, such as modesetting, memory management, and graphics rendering. The remaining bits on the X side of things are used just to interface with the X server and aren't needed by Wayland.

Can Wayland be used with the closed source proprietary graphics drivers?

No, not at this time. fglrx, nvidia, psb, and other closed source drivers are developed externally to X.org and externally to Ubuntu. As far as we know, work to update them to conform to the new KMS/GEM/etc. architecture is not planned (at least, not publicly) and would need to be done before they could be used under Wayland.

According to Kristian closed drivers need 2 things:

A way to set the graphics mode (like KMS, but it could also be a standalone library)
A way to share video memory buffers (for example an EGLImage) between processes

psb already is capable of mode setting. I (adamw) don't know if it can share buffers."
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So the question is who makes the drivers for the PowerVR GPU for each SoC vendor and which SoC vendor is Jolla going to use?
TI, Samsung or something else from Asia.

In preparation for Jolla I decided to learn more about linux and qt creator. I learned a lot in just 1 day.