This is probably a stupid question, but why would I get a jumper instead of a diode in a cherry mx switch? I could not find an answer to this in the OP.
Depends on the PCB. I don't know of any newer boards besides maybe some Cherry ones that use in switch diodes. In switch diodes only support up to 2KRO.
So with a newer pcb, say something like Sprit's GB, I would not want diodes. In this case would I want jumpers or nothing at all? If I want nothing at all, are jumpers easier to remove? Thx...
for PCB mount switches, the jumper helps to anchor the switch to the PCB. without it, you can lift the front edge a little. Many cherry KB's also used the jumper as an actual jumper, making their PCB design easier for 2KRO PCBs. the Dolch keyboard, for example, roughly 2/3 of the switches' jumpers are legitimately used. The rest only help to anchor the switch.
For sprit's PCB, I would recommend having either a plate or something in the switch (diode or jumper). Keep in mind that if you use a jumper, you will have to cut / repair traces. You can get by with nothing in the switch (I did this on my ergodox gamepad) but it won't be as secure as it could be. I don't think I'll have any issues, but be careful when pulling keycaps. Not only can the switch open, you can damage it.
So if you don't plan to use a plate, and the PCB suppors it, in-switch diodes are a good idea. They are also (from what I've found so far) about 10 times cheaper than SMD diodes.