Sometimes, one of the harder things to do in the audio hobby is to spend only what's required, even though your budget allows for much, much more.
I used to own Stax electrostatics (worked at a Stax dealer part time in college). Today I own planar dynamics (Fostex) and an older version of Apple's premium wired ear buds, before they went multi-driver.
Fostex eqs beautifully to Harman target response, Apple surprisingly well if not as amazingly well as Fostex T50RP II. Thus corrected, they sound pretty similar, with Fostex packing a bigger punch, somewhat better sense of clarity. Hopefully, latest version of T50RP offers deeper ear pads, as stock parts of my Mk IIs were too shallow and didn't seal well.
My Stax headphones were circa 1980s and I think they would not measure especially well, partly because on-ear design doesn't form a good seal, and quickly becomes uncomfortable to boot. Did get to sample the Lambda (not "Pro") of the era which was more comfortable, but if there was some special electrostatic magic to be had, I wasn't sensing it.
I also owned a set of multi-driver IEMs, and these actually measured rather poorly, with apparent phase cancellation at the crossover point. Really couldn't come up with a correction that worked well with them.
My next headphones may well be Sony WH1000s or Apple Airpods Pro, because I don't own wireless, noise-canceling headphones, and Airpods Pro now offer virtual surround audio when used with iOS or TV OS devices.