I don’t see myself using it because of the overhead that comes with it. Here are the reasons:
1. Learning another language
Even if simple, having to know 2 languages already creates overhead for you and the people you hire.
2. Specifics of buffer replication
Most of the time I use buffer-based replication with UnreliableRemoteEvents where the batch size cannot exceed 900 bytes. Buffers offer a compact way of packing the information. For other purposes, I prefer a more readable solution like JSON tables.
Also, you need to consider that the server has native code generation. Which, as said, makes buffer read/write a lot faster, and to use that to full extend, you can’t abstract it behind function calls or oop. Which requires a way different approach.
Personal opinion
I really prefer to keep everything inside the studio. In the latest years, Roblox made lots of improvements on their code editor. Especially I am happy with the new typechecker, which compares to C++ types and user-defined documentation. Through these features were already present in external code editors. Having them directly embedded with the Roblox environment makes things a lot easier for the team creation.