What, no reply to this news item featuring a strong POTY candidate ? ;)

Mateo did very good work here. Rather than stalling the community of users and developers, waiting on an event that shall basically not occur, he took upon the task of making an ASM program providing the main features one can expect from "shell" programs.
The task yielded brand-new documentation about the TI-eZ80 platform's software and hardware.
Last but not least, Cesium is open-source software :)

It's definitely an impressive effort, and MateoConLechuga has been especially gracious in his acknowledgement that different shells have different goals. Cesium was initially designed to test C libraries, and it evolved into a simple, functional shell. Other shells, like Doors C[S]E that you so obliquely reference, have focused on a much larger feature set. It's disingenuous to suggest that the author(s) of such a large shell would intentionally delay developers' work, and ignore the possibility that said developers might be spending large chunks of free time they don't have trying to convince those who could give us broader access to these devices that a complete, user-friendly shell containing libraries for ASM, TI-BASIC, and C programmers to do so. As you know, Doors CE (for example) is now progressing rapidly, but the hacks and changes necessary to support shell features in an ASM program are lengthy at best and increase the danger of an unstable shell at worse. I'm glad you hold the health and future of the community in such high esteem, and I'm sure that you recognize that everyone who participates in making it a fun, educational place is equally interested in the community's success and longevity, even if their approach might not be exactly the same as yours, or if they might not be so pessimistic about what is impossible and what is not.

I think he partly refers to how, at first, some community members had the (perhaps false) impression that the release of the TI signing key was an absolute requirement for Doors CE 9 and that no 8xp version would ever be considered, even in the worst-case scenario.

I think the lack of reply has to do with people not checking ticalc.org news as often, since there was a 7-months gap without any. It certainly got quite a bit of comments on Cemetech, TI-Planet and CodeWalrus. Same for PHASM, although I don't think it's finished yet.

The shell seems to work fine except except when a program finishes running it is returned the the shell and you don't get to see the output. You have to put a PAUSE at the end of a program in order to see the output.

Actually fairly typical of using a shell, as soon as a program ends, if it uses Return or just runs out of program, it returns control over to the shell, which usually will not wait around and displays its UI again.