I have the same experience. I learned Haskell because of the aura of prestige around it, and must admit I still love the syntax, but moved over to Clojure as my daily-driver as the practicality of "just use maps" is incredible.
IMO the article misses the point there. Immutability is the "thing" in FP.
Yes! I spent months (maybe even years) trying to understand Haskell, and for the love of god, I just couldn't wrap my head around so many things. I just wanted to build stuff with it, but it felt like becoming a doctor - getting a bachelor's, passing MCAT, then four years in medical school, then residency program, then getting a license and a board certification. All that for the sake of knowing how to properly apply a band-aid (or something). Except, with Haskell, there's no rigid structure, there's no single, proven, 100% guaranteed path to glory - it's all blur. There's no "10 steps to build a website with Haskell". And then I picked up Clojure, and OMG! everything suddenly started making so... much... sense... All the things in Haskell, for which I had either no clue or had some shallow understanding - that all became so much more intuitive.
It definitely took me at least 3 years of reading and practicing to be able to get to -at least think- understand it, and I still think I would be considered pretty incompetent by people that do Haskell daily.
There is no doubt in my mind that the Purity concept in Haskell is taken to an impractical degree. I happen to like it, but it does not make developing software with it any less of a troubled experience. The defining concept in comparing Haskell and Clojure for me is the pareto principle :D Clojure gets 80+% of the way there, without 80% of the self flagellation.
There is also a consideration of static typing vs dynamic but that's a whole other can of worms.
Simply, in Haskell all mutability is delegated to the runtime while in clojure one has the freedom and responsibility to manage it directly, and boy does it gain in simplicity for it!
I know I am preaching to the choir but it's pleasant to find a similar experience and share thoughts!
IMO the article misses the point there. Immutability is the "thing" in FP.