My experience with executives is that they don’t necessarily want yes men, but there’s a range of acceptable criticism or feedback that they’ll accept. As long as you’re within that range, it’s fine.

I'll agree with this.

If you try to address fundamental problems that might require real change… well those people tend to get suppressed.

Potentially true. I remember trying this too when I was really young in my career and getting sidelined. What I know now is that I had no idea what the hell I was talking about. I thought I knew enough, but really I just had a fraction of understanding. I had an older mentor give me some guidance around that time I didn't understand until later, but after decades in the workplace I know how I screwed up.

They’ll happily take feedback on meeting structure or project planning or whatever. But try to do a retrospective on what the true longterm costs of their decision to go with the cheap, but unreliable solution and they’ll blackball you.

There's some truth to your statement, but you may be missing the bigger picture, and at a lower level, you're not privy to information you would have needed to arrive at the decision leadership did. Your job at the lower levels is to execute on the plans of leadership. You do have a responsibility to use your mind and if you're seeing risks (short term or long term), communicate those up the chain. However, leadership may already know those, or may know about bigger risks from not moving forward you're not aware of.

Again, good leadership isn't absolute. There are certainly idiot leaders and CEOs. There are also good people that are leaders and CEOs that are just out of their depth in areas. Both of these can result in the same thing that they make a bad decision and the organization and the workers could suffer.