I've never seen any definite proof. The closest to that is that some Fuji rep did say they had "mothballed" their film production lines at the beginning of the pandemic, and there was an implication that they still hadn't restarted them at the time of the statement (end of 2021). But that was more than 2 years ago, and while it's never been in abundant supply, I've been able to periodically buy Provia and Velvia throughout that time.
+1.
Bellamy Hunt (Japan Camera Hunter) has said multiple times that Fuji is not actually producing film anymore, and he's said it as if it were definite, 100% unquestionable fact. But he hasn't said anything about how he knows that, and he's (understandably, IMO) very bitter towards Fujifilm right now because they basically killed his Fugu film project. So, I take what he's saying with a grain of salt, or at least the certainty with which he says it.
He started his campaign against Fuji long before, when they discontinued Neopan 400. That was his most used film. And he has never forgiven Fuji that they stopped it. But he has also never understood that Fuji's BW market share was tiny, and the production numbers extremely low compared to their color materials. When demand dropped, it was problematic for Fuji to stay in that market with all products.
"So, I take what he's saying with a grain of salt."
A barrel of salt would be better.....

He is a person with a very problematic relation to the truth:
In 2016 he introduced under his label the "JCH Street Pan Film". And told his customers the marketing fairy tale that this would be freshly produced film exclusively for him.
But when this repackaged stuff was introduced to the market in 2016, it was indeed old, expired leftover stock of long discontinued Aviphot Pan 400. Last coating run of Aviphot Pan 400 at Agfa in Mortsel was already in 2008.
This expired film rests were already detoriated (probably of bad storage at the source he bought it) and had very high base fog and reduced film speed.
Experienced long-term users of Aviphot Pan 400 (e.g. aerial photographers and traffic surveillance film experts like SPUR in Germany; and film enthusiasts like me and lots of others here on photrio and other film forums, especially in Europe, and facebook photo groups) immediately realized after detailed film tests of Street Pan 400 what this film really was originally.
And those who reported their test results publicly were massively attacked and bashed by Bellamy Hunt for telling the truth.
Because Hunt has told to his customers the marketing fairy tale that the film was "freshly produced" and "exclusively for him", and has "never been on the market". All that nonsense to fool his customers and to hide the scam that it was just old, discontinued, expired film offered at insane high price.
And when this first leftover stock was sold, he just switched to Aviphot Pan 200. Of course without any information to his customers. And with the same ridiculous high price (much higher than all other Aviphot Pan 200 repackaged offerings).
In 2016 he bashed all the film experts, who have been testing and developing films for decades, and who have tested his Street Pan.
And in 2017 he proudly published an article on his blog that in 2017 he developed for the first time in his life a BW film by himself.
Go figure.......would you trust someone who is acting this way?