When you use, say, Kagi, you become the customer; they have a vested interest in providing you with the best experience they can, because they know they're relying on your continued patronage to be able to keep competing with those other free search engines which you already admitted are pretty good.
As an engineer... googling for stuff is a good fraction of your job. It's quite reasonable to pay to improve that experience. The only real question is what is reasonable to pay.
Note: I am a paying Kagi customer
It also gives you exactly what you ask for. If you put words in quotes, you only get results matching that phrase. Same with +- modifiers, and all the other "advanced" search operators.
Meanwhile on any free engine, they often completely ignore your query to show you unrelated SEO slop. You can completely forget modifiers and advanced queried, they aren't even parsed. About the only thing that still works is the site: modifier. And I'm pretty sure they only keep that because 40% of google searches include site:reddit
As well, if Kagi can't find a result for your query, it returns nothing. Try searching something incredibly obscure on google or DDG. You get pages upon pages of results and they're all useless garbage or just straight up ads disguised as results.
That's why I pay for Kagi. It stays the hell out of my way and only gives me exactly what I ask for and absolutely nothing else.
Most people who complain about Google don’t even use it properly (e.g. PSE).