I disagree that this is in the tradition of projects like TinyC; I wouldn't call this project "tiny" in the same way I would call TinyC "tiny" because this project uses LLVM, which is quite large and complex.
Hehe, LLVM takes about an hour to compile on my laptop. The compiler itself is not tiny in any way. It really refers to the size of the binaries produced which is usually very small. For example, for WebAssembly, reductions to 3% of the original size are not uncommon.
3% seems common (in my testing), with 2% occasionally happening as well. ;)