If we start adding in exceptions at the top of the software stack for individuals failures of specific CPUs/vendors, that seems like a strong regression from where we are today in terms of ergonomics of writing performance-critical software. We can't be writing individual code for each N x M x O x P combination of hardware + software + workload + configuration (even if you can narrow down the "relevant" ones).
That is kind of exactly what you would do when optimising for popular platforms.
If this error occurs on an AMD Cpu used by half your users is your response to your user going to be "just buy a different CPU" or are you going to fix it in code and ship a "performance improvement on XYZ platform" update
Given that the fix is within the memory allocator, there is already a relatively trivial fix for users who really need it (recompile with jemalloc as the global memory allocator).
For everyone else, it's probably better to wait until AMD reports back with an analysis from their side and either recommends an "official" mitigation or pushes out a microcode update.
I guess that in most big companies it suffices that there is a problem with their own software running on the laptop of a C* manager or of somebody close to there. When I was working for a mobile operator the antennas the network division cared about most were the ones close to the home of the CEO. If he could make his test calls with no problems they had the time to fix the problems of the rest of the network in all the country.