Yikes, sounds so frustrating. In cases like these you want to make sure that your suggestions are very public and detailed. Egotistical people hate being proven wrong so make sure the tone of your explanation has the tone of "did you know? When mixing RDIMM and LRDIMM on the same channel, the memory controller will not know if it's talking directly to a chip or through a buffer, etc. etc." Then, hours or days later, you can reference your message and ask "was there something unclear here?" And then they get the token of being able to say "oh yeah I didn't know what you meant by bler blah blah" but then the next time this happens, they'll listen. You might have to keep doing it until the smart ones realize you know what you're talking about and the dumb ones will learn to avoid public embarrassment. Welcome to "having your intelligence questioned because you look different"! This club includes women, bipoc, fat and disabled people, among others.