Das Problem stellt tatsächlic das S36Format dar:

Display format (DSPFMT)
Specifies the format and terminology to be used on the displays that result from running this command.

Note: If the System/36 display format is used, the Output (OUTPUT parameter) is ignored and the data is presented at the user's display station.

The possible values are:

*INLENV
The format and terminology that is used is determined by the SPCENV (special environment) value specified in your user profile. If the SPCENV value is *S36, the System/36 terminology is used. All other values result in this system's terminology being used. *S36FMT
System/36 terminology is used to display the information.
Note: Spooled files which exist on primary or secondary auxiliary storage pools will not be shown when using a display format of *S36FMT.

*NORMAL
This system's terminology is used to display the information.

Da jeder Spooleintrag erst in dieses Format übersetzt werden muss, ist das System eben ziehmlich beschäftigt.

Probiers mal einfach aus mit:
WRKSPLF SELECT(*ALL) DSPFMT(*S36FMT)

PS:
Verwende beim Aufruf einfach folgendes, unabhängig von der Umgebung:
WRKSPLF SELECT(*ALL) DSPFMT(*NORMAL)