Why? I understand the author's claims that many managers are not properly suited for their job, but the author never claims that spans of control (how many people a manager can manage) are changing as we move to a fully/more remote work future.

Are people finding that managers have become more efficient in remote settings?

The author does think a lot of middle management are in fact useless, though - he's written at length on why return-to-office culture is wrong, and who's pushing it (useless middle managers) on his substack: https://ez.substack.com

Maybe some are, but that's not the point. How busy with real work product were they before?

That's a very different conversation - what is the value of having managers. Are you suggesting that companies do not need managers?

No. I'm bringing it back to the premise of the article after your efficiency tangent.

I'd argue the opposite.

You need more, as being visible to upper management might not be enough in a future where actual work output might get emphasized over personal appearances.

As managing your own underlings by their work performance is arguably harder then managing them by metrics like "she's always 9-5 at her desk" and "I do like his choice of tie and suit".

I never needed any manager.