..I don’t disagree, and it’s a really good point about getting a run on the ball but if you defend a zone it doesn’t mean you need to plant yourself in the middle of it.
I too prefer man-to-man, but tactics are so clever these days that inevitably players are blocked off. It’s like American Football. Two full backs on the post is old school, it takes two defenders out but it gives insurance. There was a transition to one on the post.
As you indicate, tactics can become too complex, too clever. If referees do their job, then man to man is fine.