There is a misconception in the article: static websites aren't guaranteed to be small and dynamic websites aren't necessarily big (in size of assets / load times).

Most of the bulk in modern websites comes from JavaScript (frameworks, tracking, ads), images, videos. All these can and are used both with static and dynamic websites.

Static websites may be mostly hassle-free for developers/devops, but they're typically more of a hassle for content producers. I don't see a convincing case for them overall, because one of their bigger advantages - that they are easier to cache (or rather: to keep cacheable when developers add stuff) upstream than dynamic websites - is mostly gone from the web infrastructure.