Google said back in June that when thinking about the mobile first index that you should try your best to make your mobile pages equivalent to your desktop pages. Yes, it makes sense, if you do not want to see substantial changes to your rankings in Google when you are flipped over to the mobile first index then keeping things the same is your best bet.
As Google rolls this out to more and more sites, more and more are concerned about the consequences around this roll out.
But John Mueller said on Twitter yesterday that your mobile internal linking structure does not have to be exactly equivalent but it should be crawlable. I guess he means, it is best if it is equivalent but if you can't make that happen, make sure it is at least crawlable?
Here are the tweets:
It doesn't need to be the same but it should be crawlable.
— John ☆.o(≧▽≦)o.☆ (@JohnMu) January 2, 2018
Forum discussion at Twitter.