I am simply stating that since there are multiple levels of discrimination in tech, and people might be victim of many of those (classism, ageism, sexism, racism, homo-transphobia, etc.), workers - and in particular victims of discrimination (but also the “privileged” ones) - should acknowledge each other situations

That sounds like you're saying the job fair should have just been a job fair for everybody. Which would defeat the problem solving that these groups have worked towards solving simply because what? Guys are left out? Is society just suppose to ignore all solutions now if it doesn't apply to the entire population? How is that reasonable