No it would not matter.
I don't know how you go from 5% to 60-70%. Or why you are so focused on who controls the supply.
60% or 70% was a hypothetical for you. I get it, you have no problem if China owned 60% or 70% of Bitcoin or any other entity for that matter.
Not that we are there yet but whenever ownership of anything becomes concentrated it's always an area of concern. Politics, diamonds, drugs, information and Bitcoin too.