The GPL requires that you do not put additional limits on a user’s rights to redistribute.
Saying “you have the right, but we’ll cut ties” isn’t really in keeping with the spirit of that.
I suspect, if it ever ended up in court, they’d agree yhat there’s no guarantee of access to future versions, but that doesn’t mean that it isn’t a shitty and cynical take that flies against what FOSS has traditionally stood for.