SOME resistance is a good thing, helps insure a clean strong spark,
but I don't think the exact value is critical, ie somewhere between 4K and 12K in either the spark plug OR the plug cap will be fine. A few here have reported no problem running both a 5K cap AND a 5K plug. But I don't think I'd do that as a normal practice.
There are some significant differences in firing a coil with a points system vs an electronic system. Mostly having to do with amount of coil primary saturation over varying RPM, the electronic system can compensate to achieve best spark while avoiding coil overheating in ways a points system can't.
A quote from;
https://www.onallcylinders.com/2022...y-in-your-ignition-systems-spark-plugs-boots/
"But as anyone who works around old electronics already knows, resistors can drift off-spec with age. In my experience, it often means the resistor will gradually increase its resistance, until it ultimately fails open and you get a complete break in continuity. (In fact,
we saw this with an old blower motor resistor a little while ago.)"
If you're interested, that's a relevant article.
This;
https://www.motor.com/magazinepdfs/052001_04.pdf goes into more depth and perhaps illustrates how complex this can be.
Short version? low resistance: long low voltage spark, high resistance: short high voltage spark.
Somewhere in the middle will suit most normal operation. It also hints at problems that random ignition hotrod parts can cause, looking at you (Mike's green monster coils), LOL
Another article hints that spark plug gaps much outside .028" to .040" can cause weird problems also.