FSDT KORD doesn't use default MSFS jetways, because it comes with its own custom Jetways, and should NOT use GSX jetways either, that's why the FSDT installer correctly excludes the GSX jetways so the custom that comes with the scenery will show.
If you are seeing default MSFS jetways there, it might be caused by not having removed the Asobo handcrafted scenery for KORD.
Note that, this doesn't have anything to do with GSX saying it's a "default" jetway.
You will always see that message in MSFS, because as far as GSX is concerned, EVERY Jetway in MSFS is "default", even if it has a custom model. Default jetway here, means how it WORKS (using the default jetway method, the only one available in MSFS), the only time you would have seen a different message, would be in FSX/P3D, because there, GSX operated jetways in very different ways, depending if they were default, or made with SODE, which is not available in MSFS so, in MSFS, every jetway is default.