I think the author is making the argument for consistency.

I actually always disliked the modeset that the author remembers fondly, but it is always sad to lose part of our history for arbitrary reasons and especially so if it breaks a ungoverned consistency.

To use your example: Real mode still exists and you can use it, and firewire is effectively the father of Thunderbolt (and granddaddy to Thunderbolt 3-4); so its removal really does feel unnecessary without additional context.

Serial mice is masochism, but people do dislike that PS/2 is gone, for good reasons.