I would argue that they are for a few reasons:

1. “Authority” status with them can change as often as daily.

2. Most “algorithmic authorities” can still be easily and heavily manipulated, meaning those who focus on working the tools can appear to have more authority than someone with true influence who takes a more natural path.

3. These “algorithmic authorities” (namely Big G) have been known to override these algorithms at will if you don’t act in accordance with the rules of the pseudo Internet police. For example, it’s well-known that they’ll eliminate or decrease your PageRank if you use an advertising model they don’t approve of (specifically because their own algorithm is faulty and couldn’t account for the natural move into paid link advertising) — if you use the model without following their own rules, they treat you like a spammer no matter how relevant the ads on your site might be — there’s no differentiation between legitimate and relevant ads that offer value and true spam. I personally saw one of my sites go from from a PR 6 to 0 quite a while back when I refused to bend to Google’s whims (and still won’t). Did the actual “authority” of the site decrease from a reader perspective? Did it suddenly have less value than others in the niche? Absolutely not. Google’s also been known to penalize sites in search engine rankings manually. So in fact there CAN be human interference with algorithmic outputs. It’s simply hidden from the average viewer / user.

I’d be incredibly disappointed to see this particular tool (PageRank) factored into anything authority-related not only because of Google’s well-documented behavior and biases but because they themselves removed it recently from their webmaster tools because they said they basically didn’t want site owners obsessing about it so much anymore. They’re not even attempting to “convince us of the importance” anymore.

The extreme inaccuracies of just about every online authority / influence ranking tool or algorithm aren’t new. They’ve been discussed in depth for quite some time following the “best” list craze that relied on them to paint a false picture of influence in the blogosphere.

The fact that most people might be naive enough to believe something that’s inaccurate just because so-and-so said so doesn’t mean the source has true “authority.” It just means society’s been dumb-downed.