Management and product owners should understand how these things work, and shouldn't ask for bogus data when they do. But teams implementing the changes should just flat out refuse when they know the request isn't reasonable.
Probably there was an SDE-2 or SDE-3 who called bullshit on it and got ignored.
I've seen these kinds of requests plenty of ways. Sometimes those asking include a design or specs because they honestly thought that was the right way to do it, other times they are knowingly asking for (in this case) a useless test to check a box. In either case, IMO the right response is to ask questions to clarify the goals and build to that, changing the provided design or specs if necessary.
I've had to play this out dozens of times over the years and never earned enemies from if, at one point I won over the PM leader that everyone on the dev team warned me about. Its all about tact and approach, assume everyone is on the up and up and just ask good questions to clarify the goals. Its hard to get mad at that unless its done in a condescending or argumentative way.
The performance tests were created to mimic user behaviour but only involved company APIs. Not third party requests. No one in the top level, cared about this bit of information. We ran this performance test and saw the the response times are almost the same so it's time to pat ourselves on the back and move on ...