It's based on the book "Daisy Jones and the Six (2019)" by Taylor Jenkins Reidby.

... Excerpt from an interview with Taylor Jenkins: The American writer on how Fleetwood Mac inspired her latest book, her fascination with LA and her debt to Nick Hornby Reid:

Do you know if anyone in Fleetwood Mac has been sent a copy of the book?

Oh God, I hope so, but I have no idea. But here’s the thing: almost nothing in the book actually happened with Fleetwood Mac – it’s a Fleetwood Mac vibe but it’s not their story. I haven’t actually ripped off their lives; I just wanted to spend more time listening to Rumours and needed a good reason to do it.

... Excerpt from All the Rumours About Daisy Jones & the Six:

So … is Daisy Jones based on Fleetwood Mac?

Sure sounds like it, huh! But no, this is not the Fleetwood Mac bio-series you’ve been craving. It is definitely inspired by that iconic band (and their iconic album Rumours), as well as the general rock scene of the era, but Daisy Jones and the Six are their own thing. If you want to see Fleetwood Mac talking about their whole situation, stick to their Behind the Music episode.

The people working on the show seem a little conflicted about that very thing. Frankie Pine, the show’s music supervisor, told Variety that the fictional group’s performance style was not modeled on any real group but also that she showed the cast videos of Fleetwood Mac (along with Grace Jones, who’s a bit more of a left-fielder). In regards to the music, Neustader reportedly told the music writers that he very specifically did not want it to sound like a “fake Fleetwood Mac album.” But Marcus Mumford, who wrote one of the show’s songs, invoked Fleetwood Mac yet again when talking about Sound City Studios, where the music was recorded, saying, “You can feel the Jackson Browne, Neil Young, Fleetwood Mac essence in those walls because so many of those records were made there.” So, basically, it’s definitely not a Fleetwood Mac biopic, but the real-life band and the fictional band are definitely similar enough that the comparison is made. A lot.