You don't have to take my word for it. Open the three next to each other, type in a search query. Only one will provide part of the results as a wildly inaccurate "overview" that somehow manages to link to sources telling you the opposite or contradicts itself inside the text box, which can also not be deactivated. Those are the results you get from Google and that alone makes quality worse, pure and simple.

More subjectively, but if you want to ignore the "AI overview" and consider that not results (then why are they on my results page?!), just look for a specific, slightly older video on Youtube, a site Alphabet themselves run. You can provide the exact title down to the letter and are in many instances going to struggle to find it with Youtube search or Googles Video Search, even when wrapping in ", etc. Kagi and DDGs video search tabs meanwhile yield the desired results. Again, this doesn't mean they are amazing or massively far ahead as Google was able to reliably provide such results in the past. It just means that Google Search has regressed, yet users stuck with it because, as I've been saying, quality (or lack thereof) has a hard time overcoming brand strength.