As an adult working in tech in the 90s, Google hit the Internet like a bomb. They were a relatively late entrant, long after most people had their favorite 2-3 they used (I was primarily Altavista). There was word of mouth, but search engines advertised heavily to raise awareness.

Then Google hit. Materially every person who used it stopped using their previous favorite search engine within 1-2 uses. It spread like wildfire. It was fast, accurate, and the results weren't cluttered (aka lightweight, aka friendly for people on dialup). Some competitors at the time were showing display ads on search results pages.

Google did not have to advertise that I can recall. It was like one day, search was like the auto market : lots of makes, types, etc. The next day it was all Google. It happened really fast in my recollection.

And to your point -- as far as I can recall, the big competitors simply did not try to clone Google. They kept their cluttered pages and did not optimize performance. Excite pivoted to home Internet via a merger with @Home.

A couple of close analogs you may have seen up close. AWS for having a lane virtually to themselves for a long time. Azure & Google & IBM etc. didn't really even suit up until AWS was entrenched reminds me of Yahoo! etc. sticking to their portal strategy well past its sell-by. ChatGPT for the speed of adoption. Google was like a combination of these two.