Sales and profits win the day. Intel and AMD are businesses. Their goal is to make a product and sell it. Both companies are doing that right now, with no end in sight. Say what you want about Intel, but the fact is that they are selling every product that comes out of their fabs, just like AMD is doing with their products. Intel still has a huge majority in market share in almost every category, even with the fiasco that has been the last 5 years, so I can not see where you say that AMD is killing them, in any category.
The bigger picture is that TSMC can not manufacture enough processors, even with the next upgrades to their fabs, to help AMD match Intel in production. They are FAR from that capability. TSMC has other customers, other products they make, and has already contracted out all their manufacturing for the near, and middle future., and that means that AMD can not gain a large amount of fab production and produce more products. AMD does not have much room to grow, but, they are where they need to be....growing, and earning more profit.
On the flip side, the accusations against Intel about being a monopoly are now dispelled, much to Intel's delight, and quite possibly to AMD's chagrin.
Here is a conspiracy theory for you. What if Intel saw that AMD was flagging and did things to help them become stronger over the years, such as a money injection, somehow? How about some accidental releases of important research, that could help AMD? Research that.
In the future, if AMD were to gain a bigger foothold in the server and workstation market, they will need to invest massive amounts of money in their software support. AMD's support is just downright horrible compared to Intel's, and that is very important to businesses. No matter how powerful your processor is, if it doesn't work, people won't buy it.