* Consumer/Partner Inertia?
* Ability to produce to meet demand?
* Support?
* Compatibility?
Once had an IT person tell me they couldn't move to ryzen laptops because the way the system presented its network interfaces was incompatible with their management software. My charitable interpretation is that there's enough programs like this that prevent AMD adoption, while simultaneously AMD never seems to be in a rush to fix firmware or software problems.
An example in the laptop space, Intel invested a lot in the marketing and designs of the Ultrabook classification. So customers ask for an Ultrabook from Dell, Lenovo, HP, etc. and those are only available with Intel CPUs. It’s taken several years for AMD mobile CPUs to work their way into high end designs.