And I'm probably not writing clearly, I'm an engineer, not a writer. However, I will try....
From my reply to you at 8:35 AM, "Obviously this is theoretical since we don't have a crystal ball." IOW, the pitcher doesn't know and this whole discussion is hypothetical.
The discussion is not about whether or not a pitcher should endeavor to throw strikes, we all agree that he should, as I've written four times now. The question from MWBATL at 6:21 PM last evening was how could the 2021 pitching staff have a 1.74 WHIP and a 5.49 ERA while the 2024 pitching staff has the exact same 1.74 WHIP but a 6.48 ERA. A rather large difference, I agree. I provided two potential explanations, both of which I think contribute to the answer. #1 is that the 2021 team allowed 1.74 baserunners/inning with the mix being more tilted in favor of walks and less in favor of hits and homeruns as compared to the 2024 team. Given the fact that both staffs allowed 1.74 baserunners per inning (IOW, you know that 1.74 batters are going to reach base in each hypothetical inning, no more, no less), it is better from a runs allowed POV for those 1.74 batters to reach via walk than a homerun. If the tilt was all 1.74 baserunners reaching via walk your ERA would be 0.00. If the tilt was to the other extreme, all 1.74 batters reaching via homerun, your ERA would be 15.66. To each degree that the mix approaches those two extremes the ERA will vary between those two numbers, but the lower ERA will coincide with the lower hit rate and the higher walk rate. The 2021 team issued more walks, fewer hits and homeruns, and therefore had a lower ERA than the 2024 team.
That is all I'm saying, I'm not arguing against pitchers throwing strikes.
And yes, I know that sequencing and luck around that could also make two staffs with equal walk rates, equal hit rates, equal homerun rates, etc. have different ERAs, but the drastic homerun rate difference between 2021 and 2024 (~60% higher) seems a more likely explanation, along with the apparent lack of errors as highlighted by the drastic reduction in unearned runs allowed.