I think you make good observations already well captured in Dead Internet Theory.

High craftsmanship however has always been a niche as any given problem will only find a small subset of customers willing to pay extra for higher than average quality.

SaaS may face the same fate as SEO only in the sense that it's hard to acquire relevant traffic at scale. As the industry matured, it slowly became harder to do it for new founders anyway.

With the open internet turning into botfest, people will turn to personal recommendations to solve their technical problems.

In my opinion, the personal network is the new true search engine.