Intel is behind in fab technology. I don't think the problem is that Intel's chip designs are what's holding them back. AMD offered better multi core performance and Intel responded with more cores as well. However, I do believe that Intel suffers from an awful corporate environment. There was a story about ISPC [0] with one chapter [1] talking about the culture at the company.

[0] https://pharr.org/matt/blog/2018/04/30/ispc-all.html

[1] https://pharr.org/matt/blog/2018/04/28/ispc-talks-and-depart...