This question Illustrates a valid point. The difference between "good" and "good enough"

If you handed me a pickup coil and asked me to test it I'd put an ohmmeter on it and verify that the coil did indeed conduct electricity. Then I'd hand you back the coil and say it works.

The reluctor flying past the pickup coil is very close in concept to a string vibrating near an electric guitar pickup coil. It generates a voltage across the pickup coil. As the tooth approaches the pickup the voltage increases. When the tooth travels away from the pickup the voltage changes polarity. The voltage curve passes through zero when the tooth is exactly lined up with the pickup coil. The electronic ignition reads the induced voltage across the pickup coil and fires the box as the waveform passes through zero.

The guys who were designing the ignition system determined an optimum range of pickup coil resistance. Within this range they can be extremely certain will work.

As years go by the designers develop more confidence in the sensitivity of their box. The allowable resistance range of the coil grows. Or, as years go by the box is made more sensitive by part substitution.
Either scenario results in a wider "good" range for the pickup.
Maybe the pickup coil manufacturer offers a discount if a wider range of coil resistances is allowed. So they test their box and low and behold it will work over a wider range.

Broadening the acceptable resistance band for whatever reason decreases the unit cost of the pickup coil.

So as the years go by the published acceptable values change.

Here's a similar example: The date stamped on a milk carton. It is supposed to indicate there are seven days after the stamped date before the milk turns, as long as it is properly refrigerated.
Yet when there are milk drives for the hungry they won't accept milk older than the stamped on date. The same for canned food, except that this is even more stupid. Some of the warnings say use before this date for best flavor. Exactly no warning exists that says eat beyond the posted date and experience sudden death. My wife collects for a food bank. The food bank will not accept food past the "best by" date. They throw that food away. Better that it go in a dumpster than feed someone, having substandard flavor.

I eat that stuff all the time; saves on the food bill. I have also eaten yogurt several months past its "best by" date. Never a problem. Of course it had been refrigerated and the container wasn't bulging.

If you like conspiracy theories, look at the best by date as a mechanism for manufacturers to sell more product.

I know, we're far afield, but I was trying to illustrate the shifting values of "good enough".

R.

PS: Saying use an oscilloscope shows how far from reality some people are. Who has one lying around?