No, execs aren't owners, but... if an exec can deliver the same or better results with fewer employees, aren't they a better exec? And if so, aren't they worth more money?

(Yeah, I know, there's lots of instances of execs who got paid huge amounts of money and delivered abysmal results...)

Boards aren't exactly dummies either. If they can see their exec isn't necessary I think they'd make moves to eliminate the positions. But that's in a world where reality meets the hype, and I don't think we're there yet. It gets weirder to think that then anyone with access to the tools and some capital could reasonably make their own company to battle it out with the big guys, but that future is a lot hazier.

Not really, not unless you're C-suite or your org size is in the thousands. When Google's looking for a VP to run a 100 person department, they care about your experience running similarly sized orgs as much as they care about your ability to achieve business results. People make fun of empire building but it's absolutely rational on the individual level.