> Does it actually succeed though?

Not sure about J, but I feel APL certainly does, at least for me - the symbol set makes it very easy to sketch out a solution.

Part of that ease is the generality of the various operators. That is the reductions and cumulative prefix can be done with any function. For example ⌊\ as cumulative min - useful as Vanessa McHale shows <http://blog.vmchale.com/article/numba-why>

kspalaiologos also shows APL enabling mathematical understanding on her blog <https://palaiologos.rocks/>

An APL equivalent of the J is +\¯1 1[(?100⍴2)] although others exist as there's no exact equivalent for J's { - see <https://aplwiki.com/wiki/From>