Being a pompous ass might feel good, especially when you think you are (or you actually are) smarter than your opponent, but it won't sway anyone. In fact, it does quite the opposite. If you're seriously trying to convince someone they're wrong, you need to be kind, be patient, and have a calm, productive discussion -- explaining how traditional vaccines work, how mRNA works, how DNA works, and so on.
Yelling at someone on a mailing list will undoubtedly push them further into their comfortable anti-vax bubble. Linus is absolutely wrong to behave this way, but then again, emotional intelligence isn't really his (or HN's for that matter) forte.