Receive RCS from Android users

I just noticed that I do not receive messages from Google Messages. It appears that they are RCS and not SMS but people who sens them do not even know they are not SMS.
How Can I receive these messages without installing Google Messages (!) ?
Thx for your help

Regain your privacy! Adopt /e/ the unGoogled mobile OS and online servicesphone

Reading around RCS seems to need a component /e/ is not shipped with, namely “carrier services”, a non-aosp google library.

There’s some talk on qksms, the /e/ messages app discussing ways to integrate, but the one linked open implementation seems not to be actively developed anymore