It's a very minor annoyance and well worth it in my opinion.

I was searching for a book quote for over a year. I tried every search engine, tried changing the terms, checking back several times every few weeks or so, but couldn't find anything even close. I tried kagi and it was literally the very first result on my very first search.

I haven't looked back and have never had an issue finding what I'm searching for since.

You pay instead of seeing ads, so they need the account. Remembers you, though, so you just login once. Plus they have a solution for incognito/private windows too.

I really like it, has some cool features.

You can create a search-link that includes your token so you can also use it in incognito or if you are logged out for some reason.

You do it once.

It is. And it's also terrible for privacy, but people do it with google as well.