There's no basis in reality for that assertion, as far as I can discern: it seems to be just the typical approach of making shit up to justify one's outrage. There's certainly been no express comment from Project Soul or Namco or any individual dev to suggest they are cutting the rest of the season two content. Indeed, insofar as they have sold probably hundreds of thousands of licenses for the season pass, that would be a legal and PR nightmare for them to do anything like that. For that matter, they haven't even indicated that the next characters are even going to be especially behind schedule.Who she talking about specifically because the devs on Twitter give the impression that Calibur is very much a passion project for them.
Now, let me be clear: I'm no fan of Project Soul's approach to promotion of their dlc content for this game: I think they are experimenting with a limited marketing budget and think that the best they can do with those limited resources is to keep a lid on things and keep people talking about what's coming, as opposed to just announcing everything at the front end like most developers do with their games (and indeed, as is done with even other Namco fighters). I think it's a dumb strategy and I can see why people would be legitimately tired of it at this point.
But at the same time, let's be clear: anybody who puts their money down on a season pass has to accept that they have no control over when that content is ultimately released, let alone how it is foreshadowed. Those licenses come with very express terms that pretty much never include a guarantee that all content will be released by date X. If one doesn't like the idea of that, they should not be buying the season pass until all of its content is released: nobody is putting a gun to their head to buy at any point before they know they can access the content immediately, and if any delay is likely to cause them angst on the back end, they should spend their money more judiciously. As far as I'm concerned, once you have entered into that arrangement, knowing the realities of digital distribution of content, your right to complain thereafter is limited: part of being an adult is knowing yourself well enough to know whether you can live with such terms before you agree to them.
And I'm not saying that companies don't accrue a certain amount of responsibility to keep their consumers reasonably well-informed about continuing support content, whatever their legal rights--it just makes sense from a perspective of keeping your customer happy, even if you don't technically owe the information to them. But again, we're not even past the median wait for a new character. And regardless, just making shit up and putting it out into the world is just plain petty and irresponsible. Not to mention counter-productive and destructive to the exact objective of promoting communication between the developers and the fan base: it's not like accusing the devs of doing things they are only doing in one's fever dreams is really going to inspire them to be more open...