Which AFAIK Apple does not use. I have RCS enabled on my Android phone but it only works to other Android users who have a compatible phone that also has RCS. Still does not resolve the OP's issue that Apple refuses to send/receive messages to/from other vendors' devices unless it is via SMS/MMS. It's a sad state of affairs indeed.

I’ve seen it posted multiple times on this very forum that carriers have not done a good job rolling this out. How is this actually going over in Android-land?

My (european) take: nobody cares. Usage of Whatsapp/Signal is higher.

In Australia it's been on Telstra for a bit. I got it working on Optus last year. I don't know what happens to other companies running over the Telstra or Optus networks though.