My experience with TCL is from scripting tools which picked it as an extension language many years ago. Tools like that have their own object-like systems and are likely not going to migrate, ever.
Maybe if TCL had a single standard OO library in the late 90s it would have been more successful? But I still think that languages with native OO constructs are much better that a shell-like string-oriented interpreter.
The quoting issues can be a pain, but if you learn to treat it like a language rather than extended shell, you learn the tricks to avoid escaping/quoting issues.