If they had to back it up then they would not be able to say it. Are you really trying to infringe on their rights to endanger lives by fraudulently claiming suitability for safety-critical applications without any evidence beyond their imaginations?

If we demanded evidence from everybody then people would not be able to sell their sub-standard and inadequate systems. Think about how much less money they would make, or god forbid go out of business, if we demanded evidence before risking human lives. No, better to just let them make unqualified, extremely strong claims with no supporting evidence or audit to protect their business. I mean, it is what we let every other company like Microsoft, Apple, and Google do, so why not?