I'd disagree there as stainless (at least in metric land) is categorized, in part, by strength e.g. A4-80 vs A4-70.
https://www.hi-tensilebolt.com.au/bolt-strength-grades-and-h...
http://home.jtan.com/~joe/KIAT/kiat_2.htm
> Honestly I think search in this area is actually extremely difficult due to all the inconsistent standards, specifications as well as random proprietary fasteners that exist.
It is difficult, yes, but not impossible. This is why some of the folks have commenting have held up McMaster-Carr's site as an example.
It does seem like large tech companies tend to take less than stellar attempts into these sort of areas because they don't hire people with the appropriate expertise.
That said I appreciate the fact they don't for a number of reasons as it's definitely something I wouldn't want Amazon to step into and stomp the competitors in the field.
I.e. I'll select a grade/class based on the mechanical properties I require, and the material will be selected taking into mind the environment the fastener is going into, any possible material incompatibilities there might be, i.e. don't want to accidentally build a battery, or select materials which gall together.
Honestly I think search in this area is actually extremely difficult due to all the inconsistent standards, specifications as well as random proprietary fasteners that exist.
I find that websites that sort by category to be better in this space, but that also assumes that you know what you want.