Wanted to throw this out there for anyone else to discover, since I didn’t find anything about it.
Discovered today that the Kinetic version of Purchase Advisor (confirmed on versions 2024.1.9 & 2024.2.8) does not indicate nor show any Approved Suppliers for a part when the approved suppliers are set at the Part Class (with none assigned directly to the part). The Classic screen on 2024.1.9 does display the data as expected.
I’ve got a Case open with Epicor with this information now being shared with development. Will update here if this ends up as a Problem.