Standard JSONPATH-Syntax please !

[MajorCGN]

Please use standard JSONPATH syntax.

I used an evaluated syntax on https://jsonpath.com/ on following JSON:

{
  "uuid": "a6ee8177-107b-47dd-bcfd-30960ccc6e9c",
  "number": "2730010",
  "shortname": "KÖLN",
  "longname": "KÖLN",
  "km": 688.0,
  "agency": "WSA RHEIN",
  "longitude": 6.963300159749653,
  "latitude": 50.93694925646438,
  "water": {
    "shortname": "RHEIN",
    "longname": "RHEIN"
  },
  "timeseries": [
    {
      "shortname": "W",
      "longname": "WASSERSTAND ROHDATEN",
      "unit": "cm",
      "equidistance": 15,
      "currentMeasurement": {
        "timestamp": "2021-03-28T22:00:00+02:00",
        "value": 258.0,
        "trend": 0,
        "stateMnwMhw": "normal",
        "stateNswHsw": "normal"
      },
      "gaugeZero": {
        "unit": "m. ü. NHN",
        "value": 35.038,
        "validFrom": "2019-11-01"
      }
    },
    {
      "shortname": "Q",

(...)

with $.timeseries[0].currentMeasurement.value and it worked.: 258,0 was given back. Perfect, easy, works as exprected.

Couldn't figure out, why i could not get same result for systeminfo., because it uses a "special" but not easier "version" of JSONPATH. Documentation and support are very very limited on this "special" way opposite to "real" JSONPATH. And most users do not want to learn exotic ways to get a single value from a JSON, when ther's an easier way.

"Normal" JSONPATH would have solved my simple search.