I mean, there will be people who are considering choosing between a 6900k/6950k/1700x/1800x and want to do some professional HPC type work that uses AVX 512, but like 99.9999% of people who buy x99 based stuff aren't professionals nor doing anything requiring or using AVX512, let alone those buying at more mainstream prices. AMD don't have to compete with every chip for every type of usage overnight to have monumentally improved, being viable as a competitive option in one area would be great, it seems they will be competitive in actually most areas, not having the absolute best FPU throughout isn't a problem.
It's also I think very likely that Zen 2 or 3 at the latest will upgrade to dual 256bit FPU pipes that can combine to run AVX 512 anyway, though again that will have very limited real world impact, the AVX512 support, the much stronger FPU pipes will allow more smaller instructions to be packaged and still improve overall FPU throughput for more normal desktop usage.