Each paper should be evaluated on its merits. A system with submission, voting, and comments (HN/reddit) is a good way to filter the wheat from the chaff. It's hard to believe this basic technology hasn't reached the scientific fields.
Part of peer review being a slow process may be fixable (although it is difficult to compel unpaid, volunteering reviewers to adhere to strict deadlines), but part of peer review being a slow process is specifically that if you do not want to rely on heuristics such as author credentials you need to take the time to really analyze a paper to avoid falling into the traps mentioned in the original article (confirmation bias, being misled by an authoritative tone etc.). And HN/Reddit votes IMHO are definitely not a good example of avoiding any of these.
That happens all the time on HN and Reddit.