The article starts out talking about a woman who is 502 lbs. Why wouldn't "lose weight" be the best suggestion? You're 500 lbs!
The important bit of that anecdote that you skipped over. Every doctor will tell overweight people to lose weight, but they also tell them not to lose it too fast, or it can lead to liver and kidney problems.
If a doctor says "lose weight", but can't actually assist you in doing that in a safe, controlled and sustainable fashion because he doesn't have the equipment, he's actually not very useful. My grandmother could tell a 500lb woman to lose weight, but I wouldn't pay her $200,000 a year to do so.
However, the key allegation of this article isn't just that doctors don't have the equipment to give first-world-quality health care to overweight people, it's that they have biases that cause them to not want to rectify that problem, even though that's as simple as buying a sturdier scale.
That's a much more serious issue. It's one of the key reasons AIDS was such a problem 30 years ago. No one wanted to treat ~~the gays~~ in the 70's, and so HIV was allowed to run rampant rather than be treated. Within a handful of years of our society realizing it didn't actually give a shit about whether people like butt stuff or not, HIV went from a terminal diagnosis to a manageable condition, because /doctors actually started taking the people it affected seriously/.