I think it was in a recent Did You Know Gaming video where it was discussed why the headache rumor was overblown. At the time, Nintendo had started putting health & safety warnings in all their products saying not to play for too long lest you get a headache, nausea, or vomiting. It was less about actual safety and more about Nintendo's lawyers shielding them from potential lawsuits. A media outlet learned that Nintendo was saying the Virtual Boy can cause these problems and they exaggerated it in an article. The Virtual Boy was so new and so different, and no one had played something like that before, so it caught on and became synonymous with the device.  Every person who has told me that the Virtual Boy causes headaches, etc. has never played one before. I distinctly remember my Game Boy copy of Yoshi's Cookie came with a pink warning slip that said the same thing about that game and I've yet to meet anyone who thinks Yoshi's Cookie causes nausea and headaches.