Actually, no, in many cases the tools are different.
Taking Stahlwille as an example, their No. 13 regular short combination wrench doesn’t make the specs, but they are reasonably priced.
Their “aerospace spec” tool is the No. 130, and although they looks similar, they are made of different steel, and more expensive, but do meet the spec.

In some cases, e.g. these short ring spanners / box end wrenches, the tools are totally different. These are not offered in the regular line, only aerospace spec.

Same story with sockets, aerospace spec ones are different steel, have different dimensions, and even look different.
Similar with ratchets. GGG-W-636 requires ratchets to have hard handles so they don’t collect contamination, as well as being resistant to all the fluids found in the industry, so the regular offerings from many companies don’t meet the requirements.
I don’t believe individual certification is a requirement, the tools just have to be made to the spec.
My original point was that, except for specialist tools such as spline wrenches, Snap On’s regular tools meet the specs, so they don’t need a separate range. The OP was asking what makes Snap On “high end” and this is one factor.
And if you need / want tools that meet the spec, the Snap On are not so costly compared to the specialist items from other makers.