To reduce the level of complexity and mitigate the risks of cross-dependencies RGB developers took a layered approach, building the technology in a modular way, where the modules are abstracted into different strata - such that the strata below know nothing about the strata above.
Overall, the development around RGB can be classified into the following fields, layered on top of each other:
Core protocol, or consensus-level development. You may think of it as of something which means the same thing for RGB as "Bitcoin Core" means for Bitcoin.
Toolchain development, which includes compilers, linkers, programming languagues and other tools. You may think of it as of Consensys company in Ethereum ecosystem.
Smart contracts issuance
Wallet, exchange and other software integration
Field of development
LNP/BP Standards Association
RGB core maintainers, but eventually ossified (i.e. no development activity)
Core protocol devs, upon final RGB/1 v1.0 release will perform only the bugfixing.
Toolchain development, managed and sponsored through LNP/BP Standards Association, will continue to produce and improve tools for other developer categories.
Schemata development consists of two main tasks:
Defining standards for API used in most common use cases.
Develop specific schemata, which may be seen as "RGB smart contract templates created by domain professionals".
The first case is covered by LNP/BP standards. Anybody can propose a new standard for a Schema (these standards are called "Schema (API) standards"). The standards are reviewed by the same process as any other LNP/BP standard, and are overseen by the LNP/BP Standards Association quite similar to how IETF oversees Internet standards (RFCs).
Development of a schema confirming to some, multiple, or even none of the Schema Standards can be performed by anybody, independently from the LNP/BP Standards Association or any other body. The only requirement is to unserstand how to develop a Schema and have the ability to write them using Contractum languague.
LNP/BP Standards Association maintains registry of the schemata, however any other body may create an independent registry, so multiple registries may co-exist. The process of adding an implementation to the LNP/BP registry is very simple: just submit a PR request providing all the necessary information about your schemata.
Due to using schemata, the development of actual smart contracts require no coders and conding: it comes down to the selection of a schema (or multiple schemata) which the contract must confirm to - and filling in the data specific to that schemata in pretty much the same way as filling in paper forms. This is done with some data-oriented languagues, like JSON, YAML, XML - or using some user interface tools supplied by LNP/BP Association or independent companies for existing schemata types (like fungible asstets, NFTs, identity etc).