Many seem to determine if a breed is cold hardy by if they have a pea or small comb, or not...to me that makes no sense at all. That has nothing to do with a breed or bird's tolerance to the cold and has more to do with less chance of a comb becoming frost bit or not~and that has many factors involved beyond the size of the comb, IMO.
To me, cold tolerance has to do with the ability to live, thrive and produce well~with allowances for winter hormonal fluctuations and their influence on laying production. Saying a single comb variety is not cold hardy is like saying a pea comb variety wouldn't do well in a hot climate. Like production levels, this is something that can be individual to the bird and not necessarily a breed trait only.
That being said, I do think it's wise to keep breeds that have a tendency to produce better in your particular climate and not try to fight an uphill battle such as trying to cull a Mediterranean breed flock to get those that will thrive well in a Minnesota winter.
Comb type does not make them hardy. I agree with that.
I agree with marrying a breed or variety with a climate. It makes good sense, providing we do not depend on preconceptions. Also that these birds are more adaptable than we give them credit for overall.
I like what I like for my area, but I would not want to discourage someone from trying what they like. Some have Leghorns in Alaska, and New Hampshires are kept in South America. That is one of the things I like about chickens. They are found in most places that people live.
I like to watch their behavior. I prefer those that are active during periods of extremes rather than the one huddled up on the roost or gasping on the coop floor. LOL. With reasonable expectations of course.