I just checked and this seems false.

Reddit propably discourages going through a profile and downvoting everything, which seems reasonable.

The posts are archived could that be the reason? I don’t use the official Reddit app but I can see hiding the vote option on archived posts

So, it’s basically Twitter.

Down votes are still there. He did hide his newer posts from his history though (mainly the AMA posted directly from u/spez). Wouldn’t want people to be able to easily find that trainwreck.