Well, depending on what you do, if performance or throughput matters, and usually it does, a 3.5x improvement in throughput means to save lots of money, so I'm sure most managers should see an advantage in that.
In this case, the engineers had a clear expectation and good reasons that something was wrong and such throughput should be possible. The arguments for that are simple enough that every manager should also understand this.
The other aspect is also latency but also here I would assume that managers should at least care a bit. They also have the old baseline to compare to, and see that it is suddenly much worse, so they should care about why that is and how to fix it.
In this case, the engineers had a clear expectation and good reasons that something was wrong and such throughput should be possible. The arguments for that are simple enough that every manager should also understand this.
The other aspect is also latency but also here I would assume that managers should at least care a bit. They also have the old baseline to compare to, and see that it is suddenly much worse, so they should care about why that is and how to fix it.