This is an incredibly bad example and a meme that clueless people (usually Europeans) love to bring up time and time again but if you watch the show carefully, you'll see that Walter actually had health coverage for his chemo therapy from his school insurance but he resorted to selling meth because he wanted the best chemo therapist in the sate of New Mexico, and one of the top 10 in the whole US, so he had to go privately out of pocket. In Europe you'd also need a boatload of cash or a top private insurance if you'd choose the best private chemo therapist and clinic in the country outside the public health system where Walter would be on long waiting lists if he were in Europe.

And reason number two, he mainly sold meth because he had a huge ego that prevented him from accepting charity for his treatment and he loved the danger and thrill of it in his mid-life crisis to compensate for being a looser/push-over his entire life holding his career back despite his scientific brilliance, nothing to do with the US health system, that's why the show's writing and character development was so good.

Anyway, pointing at a fantasy TV show as an argument for real life issues is just silly. It's not real.