It is not clear (to me) what point you are trying to make, but let me say that nothing would make me happier than if 3CX were to release their own REST API to the public. We want to do things the "3CX way". If at some point in the future 3CX releases their own REST API, we will immediately switch over to their API. But, at least for now, that is not an option.
I will say, however, that there has been no news about a publicly available REST API from 3CX for quite some time. 3CX runs a tight ship and they are very focused on building a rock-solid, scalable, feature-rich PBX and perhaps they feel making a publicly accessible REST API would pull support and development resources away from their primary mission. I'm not going to start second-guessing Nick on his business decisions. I could only dream of being as successful as he has been. I'm 64 years old, and it is not likely that I will ever catch up to his level of success.
Our REST API was born of necessity. Originally our tools were installed directly on the 3CX server. But about 15 years ago 3CX asked us to move our tools off the 3CX server and install them on a separate server. They didn't want our tools consuming resources needed by 3CX. Given that the 3CX Call Control API only accepts requests from "localhost", the only way we could move our tools to another server was to create a REST API. This API makes it possible for our tools to communicate with the 3CX API. Making that API available to the public was an afterthought and only happened after considerable internal debate here at VoIPTools.
As it turns out, we don't get that many API support requests. We provide client DLLs (.Net) that obfuscate the complexities of communicating with 3CX and our APIs, and full Swagger documentation for our REST API, and a sample Visual Studio project. I assume these resources answer most questions.