There is actually some rational ground for being suspicious of public figures who change their minds in their area of putative expertise. Nominally, the job of

There is actually some rational ground for being suspicious of public figures who change their minds in their area of putative expertise. Nominally, the job of Secretary of the X is to be an expert in X. They should have done the work to come to the correct opinions, and be able to defend them. While in theory I wouldn't want them to hold that opinion at all costs, it should be a rare event that causes them to radically change their opinions. It should take some very substantial stuff to do it. They shouldn't be someone who can be blown by the wind and a couple of stray facts, because they should be sitting on a lot more facts that support their position. Now, in reality this is all sorts of naive and the Secretary of the X was absolutely certainly not put there simply because they're the best at X. We're lucky if that was even a consideration and if they can even follow the most basic issues in field X. Nevertheless, despite the fact a number of people know that the nominal level of politics is far from the only one, it remains an important one. The nominal level of politics becomes more important the larger the group of people, and national scale is just about the largest relevant scale. Even so, even in small environments I find the nominal level of politics remains important even when every single participant knows everyone else is putting on a political show for everyone else. It's weird to me, but while analyzing that surface level is nowhere near sufficient to understand what is going on, it never ceases being relevant. So it remains relevant for people in positions of authority to have relatively stable positions. Otherwise they're penetrating that nominal level of politics, and that's a very dangerous thing for them to do. Despite the fact we visibly have a lot of people in charge of X who know basically nothing about X and are clearly there for purely political reasons, if they actually publicly admitted they know nothing about X and they're just there because of their political skill, they'd be out of a job within the week. This argument just applies to authority figures. But then, in my experience, in real life changing your mind is less of a deal; sure, that one guy or whatever might call you out on it but it is not intrinsically a huge deal. (The resulting rearrangement of relationships may be a big deal, but I wouldn't call that being mocked for changing your mind, that's a consquence of changing circumstances.)