Okay, that was confusing.
Going back to the first post... If one follows the link in that post:
https://www.mouser.com/ProductDetail/652-4120R-601-201L
Mouser lists the proper filter replacement. However, the datasheet they list as going with that Bourns part is wrong. Mouser has the Datasheet wrong. It's been puzzling me for a couple of days. If you look at the part number decode on the datasheet, which Mouser links, the middle number should just be a 1, 2 or 3. Not a 601.
Here is the proper datasheet for that part:
https://www.bourns.com/pdfs/601.pdf
4120R-601-250/201 is indeed an Resistive/capacitive network. Mouser drops the 250/ from its in house part number but lists the proper Bourns manufacturer part number. This combined with the wrong datasheet concerns me. I'm not convinced Mouser is shipping the proper part.
The part that Superjer2000 lists is just a resistor pack. It provides no filtering, although it could reduce ringing on over powered lines.
I'm not sure which part BaldGoldEagle is referring to. At one point Uniserver recommended a part that is just a resistor pack. And maybe Apple used those in some machines. So they may be good enough. However, with no capacitive element, they aren't really filters electrically speaking.
View attachment 601.pdf