Another reason is to preserve their sentimental value
For the control decks it tends to be the other way round that when they start activating their man lands you have probably lost
While it was still a playable and powerful deck, by the time Return to Ravnica hit the format, it was no longer a dominant force, which was a good thing because it gave other cards, sets, and mechanics get a chance to shine in Standard
Even Improbable Alliance, while not tied directly to cycling, works beautifully in these decks by producing a steady stream of tokens as long as youre drawing cards every turn
Attacking with your commander can be useful (because of commander damage), but it can leave you vulnerable to attacks from other players
Now how about this lore from the release announcement