Tcl is more-or-less required if you're involved with the physical design of silicon (most EDA tools only provide a Tcl interface). It's a good fit for that purpose. If you need a language which is easy to embed and you want non-programmers to be able to use it, Tcl is a good choice, though I've heard that Lua has supplanted Tcl for that purpose.
In the silicon industry it’s definitely tcl only. Zero Lua. But every tcl script I have seen is extremely simple, often just a bunch of commands to the EDA tool that reads like a list of bash commands.