You are correct. The US Club Lacrosse rankings aren't just some guy's opinions. The rankings are mathematically calculated using the results posted on the site. That's why we see funky rankings after the fall because so few games have been played. The rankings will normalize and become more accurate as more games are played. From the website . . .

Like Laxpower’s and Laxnumber’s power rating algorithm, US Club Lax’s ratings are mathematically computed based on game results in the system with no subjective weighting or human input. All games count equally over the course of a season. Using only game results, US Club Lax's algorithm computes an overall average performance rating for teams based on how teams perform against other teams and the strength of a team’s opponents. A team's overall rating then determines a team's ranking position based on the national, regional, state, and/or sub-state ranking categories a team is placed in. A team's overall rating is typically not reflective of the team's best or worst games, but a mathematically computed average performance rating that translates game results into a numeric representation of a team’s performance.

https://www.USCL.com/faq