What do you mean by Cheap Internet copy plugs?
That was several decades ago.
The first big improvement for plug longevity was Electronic Ignition. With points and condenser plugs lasted between 10k and 20k miles. Electronic ignition allowed you to use a wider plug gap. The first mod I’d ever do on any older vehicle is to upgrade a points condenser system to Electronic Ignition.
Fuel injection and computer controlled electronics helped a lot in overall performance, but little in spark plug longevity.
The next big improvement were Platinum plugs. This pushed plug longevity out to 60k miles.
Then cam Iridium plugs. With Iridium plugs they are now lasting 100k+ miles.
Please note that Iridium and Platinum plugs do not perform as well as standard Nickel/Copper Core plugs. They just last a lot longer.
And now some manufacturers (Mazda and Hyundai to name a couple) are designing a gas engine that doesn’t use spark-plugs.