Hi @smichal,
Developer on the Posit Package Manager product here. To answer your questions:
Will the missing binary packages be added at some time?
Yes, we're actively reviewing the data you've posted here. We strive to build 90%+ (99% ideally) of the binary packages for Windows that CRAN provides and should have an update soon.
Are you (Posit) striving to jump in for the retiring MRAN?
While the news of MRAN shutting down is recent, we hope Public Posit Package Manager can act as a replacement for MRAN for the community. We're reviewing any missing functionality that MRAN provides and hoping to either replicate it or have a path forward for most cases by the shutdown date.
I hope that helps,
Tyler