Where are you getting this from? Of course discussion on 4chan wasn't as politicized back then because politics was a much smaller part of the internet a decade ago in general, but people back then are still what you'd call "nazis" or whatever even today. If anything the /n/ (the first iteration of /pol/) board had existed since close to the start of the site and only in 2008 was it removed and replaced with the Transportation board.
I haven't read the links you posted but from the title it doesn't sound like either of them imply the holocaust or COVID were made up. IMO GP's comment applies doubly here, you're just conditioned to have a kneejerk reaction over any non-mainstream opinion.