This article ignores the fact that for many languages, the package repository is maintained as free software by volunteers (sometimes with funding from a foundation). This includes Perl, Python, Ruby, Rust, and many others. NPM is the odd one out, really. I don't think letting one company control a language ecosystem's single package registry is a great idea, for all the reasons that the author notes!
I agree, though it's worth noting that while volunteers can maintain the software and administer the indexes, they also rely on infrastructure provided by big corporations. E.g. the Python Package Index runs on a CDN provided by fastly, which serves hundreds of TB per day. I very much doubt the non-profit Python Software Foundation could afford that bandwidth if it wasn't an in-kind donation.
Seriously though, Fastly's donation of their CDN service is generous and eases the burden on the PSF, but if push came to shove they could definitely afford the bandwidth. In 2018 they had a net income of half a million.