I'm a software dev as well. My team has 3 backend engineers. Yesterday, I reviewed some new changes which were merged into the master branch already. I instantly spotted serious issues on them. That Pull Request was approved by a senior engineer. The FOSS community needs to a deep reflection. Human makes mistake and overlooks things.
I work on system backend mostly. Now using Go all the time. Sometimes I have to maintain a little bit on the deprecated PHP code written by someone else.
But I don't know SQL Server that much because I don't use it in work. But today, many companies are using SaaS SQL Server. So it doesn't matter on what OS it is running on.
yeah the core of the C# CLI/CLR is written in C/C++ and assembly, which is not fun to reverse engineer. But yeah reverse engineering C# or Java code is trivial