Quick sanity check: you're susceptible to pretty irresistible optical illusions which would never fool a VLM, does it mean you're not thinking? In fact, with a non-monospaced font I also have trouble determining whether these parens are balanced, and have to select them with the mouse, i.e. use a "dumb" tool, to make sure.
Reminder that "thinking" is an ill-defined term like others, and the question whether they "think" is basically irrelevant. No intelligent system, human or machine, will ever have zero error rate, due to the very nature of intelligence (another vague term). You have to deal with that the same way you deal with it in humans - either treat bugs as bugs and build systems resilient to bugs, or accept the baseline error rate if it's low enough.