I also find this conversation ironic. Don’t you usually argue that we should respect other opinions that we don’t hold of. Shouldn’t that apply to rishonim and the shulchan aruch?
I’m not saying you should say it is even ok to get drunk today, if we happen to pasken otherwise. But you cannot call the shulchan aruch backwards.
My answer to your question is that the minhag has always been to get drunk. We have always paskened that you get drunk. Nothing has changed in all those years.