Twenty years ago every PHP website had search. We forgot how to do it.

I remember that time, it was usually better to go to google and use "site:".

To be fair, the search was thanks to databases and it was usually not very good (it takes work to set correctly).

Having a search and having a functional search are two very different things though. To this day, the search on many sites is so bad that it's actually better to use a search engine and scope by site rather than use the site search.