I have no affiliation with AMD. Just own few pieces of their hardware. The following is my speculation. For what I noticed, Polaris and Vega had a brute force

I have no affiliation with AMD. Just own few pieces of their hardware. The following is my speculation. For what I noticed, Polaris and Vega had a brute force approach; you could throw a workload on them and they would brute force through it. Navi generation is more gamer oriented; it does not have the hardware for the brutal approach, it relies more on optimizations from the software running on it and using it in specific ways. Provides better perfomance for games, but worse compute - and that's why it is not and is not going to be supported by ROCm. The downside of course is, that you can no longer buy Vega. If I knew it last time it was on sale...