It seems you're implying that the argument being presented is basically just, "The world is getting warmer, aaaa!!!" There's much more to it than that. In fact, even the article you're criticizing provides a more nuanced justification than that, which opens you up to criticism for constructing a strawman argument. The real argument is, "Researchers have built detailed models to try and understand how the climate behaves, and sussed out many, if not all, the factors that influence global climate, and based on those models we can make certain worrying inferences about the current state of things and how we expect them to develop in the future."
Those models do a very good job of hindcasting global climate over the period for which we have good, detailed data. This period admittedly and unfortunately does not cover much of the Little Ice Age. In climate science, as everywhere else, the GIGO principle applies. But since we do still get non-garbage out when we put non-garbage in, that leaves us in a state where they seem to be our most reliable source of information. If you want to challenge them, it's not enough to point out various historical events that are primarily hard to explain due to lack of data. You need to be able to propose a better model.
Concrete example: Nobody threw Newton out the window just because, despite all the myriad places where his model worked stunningly well, there were a few things it couldn't explain. They waited until Einstein came up with a model that explained everything Newton's model could handle and more. And then they used that in some spots, but still mostly just stuck with Newton because the math is easier and accurate enough for almost any practical use. That's the way science works for physics, and that's the way it works for climatology, too.