Site worked fine for me, but in any case, SQLite is 23 years old now and widely used all over the place and well understood by many thousands of developers... the time has long since passed when its reputation might hinge on the moment-to-moment uptime of its own home page.
It's probably not availability issues. From what I've seen in Fossil discussions, sqlite.org is just a couple of Fossil instances (code and documentation) and a pack of HTML pages behind a simple web server. They had to invent an ad-hoc scrape protection for computationally expensive requests, and probably have something like that for DoS protection. It is possible that it is not fair because of simplicity, and temporarily blocks certain amount of less lucky visitors. Intermittent inaccessibility of project websites seems regular to me.
