One example that comes to mind is the delimited continuation primitive (what Guile calls a "prompt" [0]) that would allow for lightweight concurrency in elisp code, something that elisp is not good at today.

[0] https://www.gnu.org/software/guile/manual/html_node/Prompts....

there is a presentation on youtube (a new one)

https://www.youtube.com/watch?v=yjC162DnsKI&t=594s

for me the most interesting point, guile will allow emacs to be more lispy, replace c code with guile code and integrate with CLISP and CLISP libraries

Probably nothing, but then this feature isn't aimed at people who have used emacs for years, and who like and effectively work with elisp.

I on the other hand, am very familiar with guile, I don't particularly care for elisp, and I would like to be able to customise my editor more comfortably. For me this is great.

Have a runtime separate from emacs where you could use things like "liborgmode" comes to mind.

Maybe tighter integration with guix? So that you can control your entire os (you’re using exwm right) just using one language

Multitasking