What brought that about? Primarily Taylor Guitars, but many other fine builders are adapting to the bolt on neck. There's arguments either way regarding bolt-ons vs various tenon/dovetail connections, and maybe that would make an interesting thread sometime. Bolt-ons are easier to service and faster to make etc, or so I'm led to understand. Given the price of Taylors these days, it's hard to make an argument for it being cheaper.
I hope this next statement doesn't offend anyone, but it's a general caution. Do not believe everything you read about guitars on the internet! The advantage to this forum is that if someone posts something really ridiculous, others will issue their dissent. On most sites there is no authoritative editor, no checks and balances, so alot (!) of pure unadulterated crap is sent out into cyberspace. Bad tabulature, chord changes, and advice. At best we get illinformed opinion, at worst unknowledgable and dangerous advice. There are some decent sites, but they're outnumbered by wannabes. My guitar students often show me stuff they can't understand, or stuff they will have to correct.