Give AMD a break..
AMD had basically ZERO experience with anything related to Edge, and not a lot of experience in IoT/Embedded. Most of the time, mind you, their embedded solution (prior to Zen based CPU's) was just a desktop CPU. AMD made most of it's money from the semi-custom: Sony, Microsoft etc..
Yes, the EPYC for embedded is quite old, but AMD needed something that can have some good & tested architecture - like Zen 3, something which will they need to support for at least 7-10 years, can have tons of core and tons of memory, be cheap, be reliable - enter AMD Siena (already available to some major OEM's, btw), which should compete directly with Xeon D or anything based Ice lake and probably Sapphire Rapids (if Intel will ever release those chips...)
The Ryzen Embedded is for customers who needs the basic stuff - 4 cores are more than enough, cheap, has a long official support (10 years) from AMD. The OEMs seems to like it. Yes, it's not based on Zen 3, it's based on Zen+, but in this segment, you roll your own board with an ODM, and you add your own custom/3rd party IP if you need something fast.
All in all - yes, Intel still rules the market, but I'm pretty sure that both ARM based solutions as well as AMD based solution - will take market share from Intel. We've been there before on other segments.