So many inaccuracies in that article, I don’t know why you bothered linking it. You could have just made the privacy/single point of failure/web monoculture argument and tossed the rest.
Because it's their article and they try to get people to use their BunnyCDN affiliate link instead.
Yes, some problems can be solved, e.g. the non-indexing of pictures. But this requires a paid account. Face it. Most people use it as a cheapo CDN. And it is just not worth it.
Many plug-ins are incompatible with cloudflare, e.g. Multisite. You will basically start building your site around cloudflare.