This is how I feel about C/C++; I find Rust a lot easier to reason about, modify, and test, so I'm always happy to see that something I'm interested in is written in Rust (or, to a far lesser extent, golang).
> So for me the less entrenched Rust remains the more ability I keep to work on the software I use.
For me, the more entrenched Rust becomes the more ability I gain to work on the software I use.
> if Rust is going to continue entrenching itself in the open source software that is widely in use, it should at least be able to be compiled with by the mainline GPL compiler used and utilized by the open source community
I don't see why this ideological point should have any impact on whether a language is used or not. Clang/LLVM are also open-source, and I see no reason why GCC is better for these purposes than those. Unless you somehow think that using Clang/LLVM could lead to Rust becoming closed-source (or requiring closed-source tools), which is almost impossible to imagine, the benefits of using LLVM outweigh the drawbacks dramatically.
> A piece of software, open source, written in Rust is equivalent to proprietary software from my perspective.
This just sounds like 'not invented here syndrome'. Your refusal to learn new things does not reflect badly on Rust as a technology or on projects adopting it, it reflects on you. If you don't want to learn new things then that's fine, but don't portray your refusal to learn it as being somehow a negative for Rust.
> I will always prefer software I can control/edit/hack on as the key portions of my stack
You can control/edit/hack on Rust code, you just don't want to.
To be blunt, you're coming across as an old fogey who's set in his ways and doesn't want to learn anything new and doesn't want anything to change. "Everything was fine in my day, why is there all this new fangled stuff?" That's all fine, of course, you don't need to change or learn new things, but I don't understand the mindset of someone who wouldn't want to.