Google's RCS has 800M active users and it's projected to hit 1B by the end of the year matching iMessage's usage. Whether people actually know that it's RCS or not, it's been a pretty successful service for Google so far.
That's actually strange. Google said a while back that all devices with Google Messages installed should be able to use it regardless of carrier too.
The one bug that I've had for a long while now is the "auto resend as SMS" feature that's supposed to kick in if the RCS chat fails, takes forever to work. It's much faster to just manually hit the send as SMS option if there are issues going on.
It uses the Signal protocol for its encryption so they went with a well known and proven option, but metadata isn't encrypted like it is with the actual Signal app apparently so it's not quite as secure.
A good chunk of my family uses Android and all have RCS enabled so I get to use it a good amount and it's been pretty solid for me.
Edit: the desktop app is actually just a PWA website so that might be able to get around your work PC's restrictions on installing apps.
You should also be able to swipe on the message to direct reply and send reactions too
I loved Android's 3 button nav for years but after like a week of using gestures I couldn't go back. Once I got the hang of it, it was way more fluid feeling to use.