I imagine that (at least) 2 things have happened to Google Search.
1. SEO content farmers have filled it up with low quality results.
2. Google used ML to tune the system and it optimized for the lowest common denominator, incompetent searchers.
The average person never learned how to construct succinct search queries and so habitually enters too little or too much into the search box. Current Google Search wants to help the poor searcher so it adjusts their entry, or in some cases rewrites it completely, before processing it and returning results it has decided that they really want.
1. SEO content farmers have filled it up with low quality results.
2. Google used ML to tune the system and it optimized for the lowest common denominator, incompetent searchers.
The average person never learned how to construct succinct search queries and so habitually enters too little or too much into the search box. Current Google Search wants to help the poor searcher so it adjusts their entry, or in some cases rewrites it completely, before processing it and returning results it has decided that they really want.
edit for clarity