> "tool of thought"
I felt compelled to make a comment about that last week[1]; I stopped thinking of it like "APL is a tool for thought [and nothing else is]" and started thinking of it like the Sapir-Whorf idea; all programming languages and mathematical notations are tools for thought and we don't normally talk about them like that. Their designs promote/encourage/ease some ways of thinking about problems and reveal some patterns in the data and the algorithms, and on the flip side by making design choices they necessarily demote/discourage/frustrate other ways of thinking and obscure some patterns.
It's not just that Go has Goroutines in it as a technical feature, it's that having a first class way to express that feature encourages Go developers to think about solving problems in terms of Goroutines. A bit like "if the only tool you have is a hammer, every problem starts to looks like a nail". But we still go down the direction of making a kitchen-sink language which has a bodge of half-implemented mismatched features from different areas wedged awkwardly into its syntax, and then saying "this company only does Java" or "only uses C++" instead of making smaller simpler tools that fit particular problems and working on ways to learn about them and integrate them.
> "I wish multidimensional arrays were a first-class citizen in my main languages though."
It has not helped you but you wish you had access to it because it's changed the way you think? Same; it has changed the way I think about bulk-transforming arrays of data, and using intermediate array structures, and thinking it's good to have an interpreter layer which transforms a whole array using SIMD/vector extensions instead of a loop which does individual non-SIMD tests on items so it can exit part way through the array to "save time".
[1] https://news.ycombinator.com/item?id=46183808