What I’m hoping is that they are still working on ripple editing and that it will be available for Nuendo 13’s release, and they’ll add it to Cubase 13 in a few months… again, crossing fingers. 
But yeah, they have said no more X.5 releases if I recall, so who knows when/if/what will happen. Main thing is that they have already acknowledged that ripple editing is important, it’s just a matter of time before they implement. Perhaps they needed to work on the framework first to accommodate a ripple editing feature? I remain cautiously hopeful but also realistic.