Well, TCL is not a good language for configuration files imho. I'd favor a declarative approach, because you can analyse (hence debug, check, etc) it better. Inspired by Prolog, but change the syntax. A configuration language should also avoid features like "eval", though Turing-completeness is probably desirable.

Nevertheless I agree that standardization is a problem. Not for the "linux community", but in general. Some people do not require Turing-completeness and (reasonably) do not want it. Others already have a scripting language (Lua,TCL,Python,etc) embedded, so reusing it is a good idea.