Do commentaries maintain that Universal monarchs and Buddhas can't exist simultaneously?

The Story of Kāla, son of Anāthapiṇḍika [Verse 178] (wisdomlib.org))

The tradition states that no two of them will appear in the world at one and the same time. A Buddha will not appear when a universal king reigns, nor will a universal king arise when a Buddha has appeared on earth.

I was reading this passage and was rather surprised to see that the tradition maintains that Universal monarchs and Sammasam Buddha’s can’t exist simultaneously. I know the suttas say there cant be two universal monarchs and Buddhas at the same time in the same world system, but i’ve never heard of a universal monarch disqualifying the possibility of there also being a Buddha. Is this actually in the commentary or is this just a bad summary on the part of wisdomlib?

If thats the case, this seems like a contradiction of the Cakkavatti sutta where the universal monarch of the time of Lord Metteya is supposed renounce his throne and ordain under him.