I drove by this today. The linked streetside view does have an opening in the guardrail, but the opening has no road/trail and only provides access to the farmers field. Also, it is not at the location of this note, but rather it is north on the road at 41-8-2.06 N, 74-45-55.85W (if my camera's EXIF data is accurate enough). See the image below, which unfortunately did not capture the guardrail opening.

https://imgur.com/a/PtyPcBE

Regarding the trail at the note's marked location, it definitely does not connect to Morris Tpke, and there is no opening in the guardrail to allow any access either and no visible road/trail whatsoever.