I did notice one oddity with RCS on Apple, namely that initially it could not be enabled if the device was in Lockdown Mode. In one of the recent updates, 18.x for some lowish value of x, that was fixed, and so my iPhone now has RCS enabled.
However, I found that Apple have screwed another part of Lockdown Mode as of 18.7.2.
If a website makes use of Javascript, and is viewed in Safari then the page reloads a couple of times then crashes with no content but an error message. That can generally be fixed by turning off Javascript in Settings, or by turning off Lockdown mode for that specific web page - rather defeating its purpose.
However, I found that Apple have screwed another part of Lockdown Mode as of 18.7.2.
If a website makes use of Javascript, and is viewed in Safari then the page reloads a couple of times then crashes with no content but an error message. That can generally be fixed by turning off Javascript in Settings, or by turning off Lockdown mode for that specific web page - rather defeating its purpose.