As is often the issue with articles like this, it discusses salary rather than compensation (sourced from Glassdoor). Since compensation at the high end is disproportionately in equity (or in finance, bonuses), this makes the range of compensation look artificially small. Differences between e.g. junior and senior devs are probably bigger than this article lists, and I suspect there might be bigger differences between Europe and the U.S.
On a related note, I feel like there's a huge range of different job categories lumped into the title "Software Engineer/Programmer". If three teams were respectively building the front end to a website, an embedded system, and a machine learning compiler, they will probably not have much overlap in senior candidate pools. Has anyone done an analysis of compensation trajectories among different specializations of programmers?