Some 3rd party but a lot from social media or what I'm guessing were PR pieces being pushed out to some of the media.
3rd party and "what you're guessing." Neither of these claims are particuarly compelling.
No that's the thing. It's the reason they failed because Chibnall and others didn't think much beyond that they went "We have a diverse range of people, that's all we need. The thing being the moment anyone objects to the characters etc people they just cry bigot / racist / sexist to try and shut them down and present all those objecting as "Not the real fans just angry Alt-right Nazi bigots."
And your source for Chibnall thinking this is...?
Look, I'll grant you that occasionally, I've seen content creators act like this, but on the flipside, what you've just said is indicative of a trend I've seen in media for close to a decade. It often goes along the lines of:
1: Character X is bad.
2: Character X is outside the 'norm'
3: Character X is an example of "forced diversity" - creators are shoving this down our throats, they're pandering to SJWs, all the problems of the character would be solved if they weren't 'woke.' (in other words, if Character X was in the 'norm,' all the problems of bad writing magically wouldn't exist)
This is a case in point. As I've made clear, I'm not fond of Chibnall's companions either, but the reason I'm not is that by giving Thirteen three companions at a time, Chibnall was stretching the time available to flesh them out thin, so whereas Davies and Moffat kept the companion no. to 1-2 at a time, and usually starting off with 1 and then 2 (e.g. Rory joins Eleven after Amy), Chibnall just dumps us with three. As to why he did that, I don't know, but my guess is that he was harkening back to OldWho, where it was common to have multiple companions at a time, and like Old Who, this made it harder to flesh them out. A lot of Chibnall's run has used OldWho as an inspiration, but whatever the case, I don't think his run has been good, and if anything, his attempt at carving his own path (Timeless Child, Flux) has been a disaster.
So, yeah. I don't think Chibnall's companions are good either. But it takes a really strange line of thinking that the reason they're not is because of some insidious agenda. Oh, and in case you're wondering, I think the idea of making the Doctor a woman was stupid for a variety of reasons, but to be frank, if Thirteen was male, all the issues with Thirteen would remain. And on the flipside, no-one cares about Sacha Dawan being the Master because, spoilers, he actually does a great job of it. So when someone outside the 'norm,' it's all well and good, but when they don't do a good job, the only reason is "forced diversity?"
Oh, and if we ARE talking about diversity, try and write Demons of the Punjab without Yaz being Pakistani for instance, or Rosa without Ryan being Black British. Neither of them would be able to function in their final form. I'm not sure how that's a bad thing.
I'm hoping T Davies fixes the mess that Doctor Who has become.
I hope so as well, but I don't think our diagnosis for the reasons behind the mess are the same.