Haha I think the opposite, this chapter add on other argument to Shanks being stronger.
COC is now known to be useful in battle.
before they were all saying : COC is lame, it has no use in 1 vs 1, Shanks has better COC than Mihawk maybe but Mihawk still stronger because COA COO matters more etc etc.
i think you can check back all the debates and not a lot denied Shanks to have a better COC than Mihawk.
But now COC is useful (not really a surprise) and suddenly Mihawk has a godly COC too.
Mihawk is strong no doubt and Mihawk Hali is likely overall monstrous but Shanks COC has more chance to be better than Mihawk one than the opposite.