How would you emulate a resistive sensor?

I’m trying to fake a few basic resistance-based sensors (thermistors, etc.) for testing some boards.

Right now I’m just swapping resistors to hit whatever value I need, which works but is annoying.

Is there a cleaner way to do this electronically so it behaves like a real passive sensor?

Are digital pots actually usable for this or do they usually fall apart because of voltage/current limits and resolution?

Or is the better approach to not even try to be a true resistor, and instead fake the signal with a DAC/op-amp and just mimic the curve the MCU expects to see?

I’m also curious how commercial sensor simulators do it. Do they actually emulate resistance electrically, or are they just injecting the expected voltage?