100's of Klines of code in continuous development over the last 10 years, still currently maintained and continually adapted for new use cases in Electronic Design Automation (EDA) for logical and physical chip design and verification.
Of course it's possible to create "write-only" code in tcl. But tcl is hardly unique in that respect. Good code design and coding practices help to avoid most issues just as in many other languages.
"Everything is a string" (EIAS) is not what leads to a complete mess; it's failing to go beyond an initial, superficial understanding of the syntax and language capability and general lack of discipline that lead to un-fixable messes.
Many of the big EDA (Electronic Design Automation) tools continue to use tcl for the command line interface. Some users have created quite complex, customizable design flows spanning multiple tools and even development infrastructure (much, much more than just "stitching tools together) using tcl.
> It fakes having numbers, which works, but has to be slow.
This hasn't been the case for 25 years, since the 8.0 release.
Tcl will store data internally in whatever format it was last used, and only convert if needed. Good coding practice pays attention to this to avoid "shimmering" a value back and forth between different internal representations unnecessesarily.
> It lacks arrays;
It does have associative arrays; and lists when used appropriately can fulfil many roles that would otherwise have been implemented in an array in another language
And tcllib[0], a collection of utilities commonly used with tcl, provides support for a number of different and complex data structions [1], many of which are written in C, not just more tcl scripts.
It's worth noting that Stallman's criticism linked above is more than three decades out of date. As with any programming tool, once you go beyond a superficial understanding of basic syntax, it can serve as a a very expressive and sufficient language.
The perception that ADHD is nothing more than the inability to "sit still and pay attention" is very wrong and very out of date. Before you comment further I would strongly recommend you watch a series presented by one of the leading researchers in neurological basis of ADHD, Dr. Russell Barkley, called "ADHD: "The 30 Essential Ideas Every Parent Needs to Know" [1].
I struggled with many of these things -- primarily time blindness, executive function and impulsiveness -- for most of my almost six decade life, and finally understanding what was happening -- and getting help for it -- has been life-changing.
As one friend put it, he would cut off his left testicle if it meant having working executive function. The idea that I -- and friends and acquaintances who share similar experiences -- are faking it is ignorant and insulting. That you do not suffer is a gift; be grateful. Maybe don't be so dismissive of the struggles and suffering of others.