The reality is that cost is the primary constraint for the public benchmark we provide. While we run enough samples to get results that are generally quite accurate on average, we only produce ~10 coding submissions per language for each model and those are across random environments, which naturally has noise. Plus that's split between agentic coding sessions and one-shot coding.
So just adding a language or tag filter can result in some pretty small sample sizes. You can see how many samples survived in the box plot, but that's probably bad UX that most people never see. There's a reason no other benchmark provides this type of data (even for our sample sizes it runs almost 10K USD/month to keep up to date with new releases).
Might be a good idea to reduce the ability to apply filters into a cohort with less than ~20 samples -- not the first time we've gotten that feedback. Seems like adding too many options to see individual sample variation is just misdirecting. I'm a nerd who loves data so I hate removing access, especially since the aggregate performance is very interesting (averaged across all languages, we see consistent and interesting performance data across models, like models outperforming with strongly typed languages). But tbh I think you're right and we'll try limiting filters to where we actually have statistically significant data.