Are they responding to: “I’m still not convinced that labs are training for the benchmark—if they were, I’d expect much better results.”

Respectfully, did you? The comment was specific to doubting the believe simonw has that labs are not training [0] specifically for this task, which is exactly what simonw wrote in the post [1], that it is a believe of his that they don't. He did not mention any kind of evidence or any piece of information that would indicate that the commenter didn't read the blog post.

Did you read either the post or the comment it was referencing?

On the note of training on SVGs, I have seen some labs models outperform when prompted for SVGs of certain animal and action combinations (pelican on bike, panda eating burger, etc.) compared to other similarly outlandish prompts for SVG output that are not part of widely reported benchmarks, even shared evidence one of the last times this came up on here.

[0] ... incredible Simon still believes ...

[1] I’m still not convinced that labs ....

Clearly not. There's a subset of HN users who rush to post this same thing every single time.