Now, maybe this is fine for someone who manages other executives, where the primary touch points can be, like quarterly budget and strategy reports or something (I honestly have no idea what people like this do day to day, so I'm totally guessing on this...).
But out near the "leaves" of an org, managers exist to support their reports who are doing work day to day, and they can't do that if they have too many reports to spare any time for 1:1s with them.
I think PMs having a bunch of 1:1s, likely comprised mostly of status updates that could be done asynchronously, is a different problem, that we likely agree about.
But managers should have few enough reports that they're able to support them. If their reports want to cancel their 1:1s because they don't have anything to discuss, that's fine, but being unable to get on the schedule regularly is a problem, IMO.
In fact I see this with my coworkers, especially PMs, who have their schedules full of 1-1s daily. No doubt there's useful work that gets done in them _sometimes_, but I have doubts its efficiency over the long term with cross functionals. But even just focusing on 1-1s between managers/reports, I'd prefer nixing them in favor of a flatter structure, and using office hours/one-offs when needed.