For people who are accustomed to cold brew (we always have cold brew in the fridge and grounds steeping) there's a very large difference in flavor and profile using the same beans. This also translates when it's heated, although I will say I don't do that often because I enjoy it cold more than hot.
I'd disagree though that it's "extreme". There are local chains in my area (Midwest - US) that offer a variety of hot cold brew drinks that are quite popular offerings. I was pleasantly surprised when I ran across this more than a year ago. But I still do run into a number of coffee shops where baristas fail to understand the difference between cold brew and an iced coffee. There's really no comparison when you're explicitly looking for cold brew. It's also often hard to find available in the winter months in my region. Not sure why, but to me that's akin to pausing ice cream sales because there's snow on the ground. Just because it's a cold drink doesn't mean I don't drink it during cold weather.
I'd disagree though that it's "extreme". There are local chains in my area (Midwest - US) that offer a variety of hot cold brew drinks that are quite popular offerings. I was pleasantly surprised when I ran across this more than a year ago. But I still do run into a number of coffee shops where baristas fail to understand the difference between cold brew and an iced coffee. There's really no comparison when you're explicitly looking for cold brew. It's also often hard to find available in the winter months in my region. Not sure why, but to me that's akin to pausing ice cream sales because there's snow on the ground. Just because it's a cold drink doesn't mean I don't drink it during cold weather.