He's lied several times about various things and, while I can try to give him the benefit of the doubt and say that maybe he misspoke or genuinely didn't know he was lying, my biggest issue is that he doesn't offer corrections for these things when he's called out by people and the videos with the lies and misinformation are still up and continue to get views.

A big one that comes to mind is his remarks on the PCKompaniet case where he continued to say that Apple was suing a mom and pop repair shop for doing third-party repairs that weren't authorized. Not only did Apple not sue them for doing repairs (they sued them for copyright infringement and counterfeiting) but people repeatedly showed Rossmann that the store owner had actually advertised the parts as "genuine OEM" parts on his website and had only changed that advertisement after his parts from China were seized (the page was archived by archive.org).

Another one was a story that was similar about parts being seized by Apple in the US (that actually, at one point, dealt with Rossmann directly as it was his order). Apple didn't seize anything, it was U.S. Customs that seized the parts because the import documentation didn't match and the batteries themselves had Apple logos on them and they contacted Apple to verify the authenticity of the parts. Rossmann continued to claim that Apple had seized the parts as retaliation and continued to claim that they were "original parts" despite actually coming from grey markets in China that refurbished and replaced components (which, legally, make them non-original parts).

Overall, the sad thing is that I agree with him on the general right to repair argument but I feel like he purposely misrepresents certain things to garner sympathy from the right to repair "movement" and I feel like that hurts the movement as a whole. I feel the same way about Linus Tech Tips and their mischaracterizations. If your argument is sound and your principle is strong, you shouldn't need to do that in order to make your argument.