Clickbaity title on the original article, but I think this is the most important point to consider from it:
After getting to 1% in approximately 2011, it took about a decade to double that to 2%. The jump from 2% to 3% took just over two years, and 3% to 4% took less than a year.
Get the picture? The Linux desktop is growing, and it's growing fast.
And even though I have seen that the average price of machines with Linux preinstalled may be close to some machines with Windows, I would guess that most people are going to go with the latter. Easier access to purchase one, familiarity etc.