Google is both the most dominant it every has been and the most vulnerable it has ever been, at the same time.
From what we've seen with GPT-3, we can train one machine learning model by ingesting the entire scraped web and a whole lot of (online/offline?) books, and it can often produce correct answers to questions. The accuracy of those answers, presuming the questions are not subjective ones, is only going to increase. Google's status, as a search engine, in 2025 is not something I would bet money on.
The iOS/Safari thing is another issue, which perhaps other anti-trust regulators will address in Google's favor. Assuming they do not, consider that if Google stops paying Apple many billions of dollars a year and another company (or Apple) replaces the default iOS search, Google's search ad business will be severely and irreversibly damaged. Removing iOS defaults would not only remove a large chunk of Google's US mobile search traffic, it would be the more affluent chunk. Everyone who knows about marketplace dynamics knows how damaging that would be to Google if that inventory ended up with Microsoft or Facebook.
Even without regulatory intervention (which is almost 100% guaranteed at this point, barring some act of god, though I don't know how large that intervention will be) Google's days atop the mountain are certainly drawing to a close. Perhaps the ground has already given way, they know it, and the maniacal stupidity of trying to coral the web into some AMP graveyard is a reaction of desperation.
To address the original blog post, I think the author is way off the mark on video. Youtube is big, but far from the king. Google has repeatedly flopped on the social side, and isn't going to be allowed to buy TikTok. They don't appear to be taking any ground paid streaming services like Netflix or Amazon. They are big, but no where near as important relative to their dominance in search.