It adds 2ms to the boot time on modern hardware, and the list it is sorting has grown by about 2 orders of magnitude since it was introduced. Seems reasonable to me that it was unnoticed.

I think the comment you are replying to was referring to the openbsd issue that apparently adds 10-20secs per boot in the GP comment.

I am currently at work fighting the same class of problem. Bad pattern was used a few times, seemed to work. So it was used twenty times, still no problems. Now it’s used 100 times and it was 20% of response time. Got that down to half in a few months, now it’s a long slog to halve it again. It should never have been allowed to get past 3% of request startup time.

Because none of the people afflicted have done anything about it.

Likely because none have the required proficiency. I certainly don't. "So? It's open source. Stop complaining and fix it." is never a good response to a bug report. I know this quirky behavior has been brought up a few times by other users than me on the openbsd-bugs@ mailing list during the 10 or so years since I first observed it.