I used to work at a commercial website host where the primary product they sold was "promo pages for your xyz business and abc products" and each and every single page was manually updated down to the head/footer and statically served. They had "templates" in a notepad, and you copy and paste it out and edit as needed. Which means that after you make the initial creation, any subsequent edit (including things like headers, meta tags, etc) needs to be done by hand. This product was still being sold very very recently, and they have a lot of clients (like in the hundreds of millions of dollars of revenue)

I wouldn't be at all surprised if AutoTrader used manual editing for everything, with no access to scriptability.

Not everyone is using jekyll or any modern stacks ... the echo chamber is strong here. I guarantee you 65% of the Internet is still being edited by hand.