The streamer has acquired the rights to the show outside of the UK and has reportedly also injected some extra cash into its famously low budget.
Returning showrunner Davies told GQ that he believes Doctor Who is ready to move forward and says spin-off series are very much a part of that, pointing to multiple spin-offs during his first tenure on the show.
"I thought — with no criticism whatsoever towards the people who were running it at the time, because they were running it within the BBC's measures — it was time for the next stage for Doctor Who," he said.
Davies added: "I thought the streaming platforms are ready, the spin-offs are ready. I always believed in spin-offs when I was there. I did Torchwood as a spin-off, The Sarah Jane Adventures as a spin-off.
"Those spin-offs declined when I left, and I can see why. And I very much left after 2008, when the money became scarce.
"I think that's fair enough for the public service broadcaster that the money is spent on other things."
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Davies said the increased budgets are very welcome, but said that figures in news reports suggesting £10m per episode were way off the mark.
"It was the BBC's notion to go for a streamer [Disney+] to invest in the show worldwide, which I completely agree with," he said.
Davies added: "I mean any piece of television costs millions. We're not allowed to talk about budget, and we're not on that Star Wars or Star Trek level, but it's more than I've ever had to work with."
The returning showrunner takes the reins of Doctor Who this year, with a series of special episodes due to mark the 60th anniversary of Doctor Who in November.
David Tennant will play the lead role in those episodes, following the shocking regeneration which saw Jodie Whittaker replaced by the star — 12 years after he previously said goodbye.
In the wake of those specials, Sex Education star Ncuti Gatwa will receive the keys to the Tardis, alongside Coronation Street actor Millie Gibson as his travelling companion.
Watch: David Tennant and Catherine Tate mark Doctor Who Day