It really depends. Mostly on how strong your iced coffee is. With that said, caramel macchiato and iced coffee are two different beverages with entirely different ingredients. So it's hard to give a straight answer on this one.
When it comes down to it, it really depends on how many shots of espresso are in your caramel macchiato. In a venti caramel macchiato, there are three shots. So, in this case, yes, it would be more potent than a cup of iced coffee. Cold brew coffee will be stronger, however, than regular iced coffee.
If you want a drink with less caffeine but still want the same size, you can always ask the barista for fewer espresso shots. It will taste slightly different, with fewer coffee flavors and sweeter.