I’d tweak it to say that a foolish consistency is the absolute worst design principle. All things being equal, consistency is a good thing, but it sometimes gets prioritized to the point of absurdity and becomes counterproductive.

There are two different things that can be called consistency.

Visual consistency means that your app looks as similar as possible across platforms. Regardless of those platforms' native UI. It's the bad kind.

UX consistency means that your app behaves the same across platforms, but adopts their style and conventions. You actually want this.

I think the core issue here is that consistency bounds are arbitrary and some people tend to push to much on these. Finding the middle is hard and is political. Arguing with UX or QA whether previously unrelated features on different screens should behave the same is exhausting. That's why I prefer small projects where I am the only customer or all users are extremely aligned (internal developer tooling).

It definitely isn’t. It’s good in many contexts, but zealous adherence to some pithy design principle without consideration is bad engineering and bad design.