😀 yeah it made sense to me because I grew up in the changeover.

But here's the Wiki entry.

The "idiot light" terminology arises from popular frustration with automakers' use of lights for crucial functions which could previously be monitored by gauges, so a troublesome condition could be detected and corrected early. Such early detection of problems with, for example, engine temperature or oil pressure or charging system operation is not possible via an idiot light, which lights only when a fault has already occurred – thus providing no advance warnings or details of the malfunction's extent.

Oil pressure tells you if the engine is dying or if the Oil is breaking down or overheating. I'd take it over an RPM gage.

A lot of vehicles dont have it in their cluster menus these days.

I drive a 10 year old Vauxhall and it definitely does not have it. I wanted to know my oil temp and had to resort to a Bluetooth obd plug paired to my phone.

I rest my case.

What's more important than oil temp?

Speed is only relevant when there's a cop around, otherwise im driving safely with the flow of traffic, the speed in mph is irrelevant. The RPM are important but I can hear it, don't need the number really. But the oil, i need to know because i would have no idea if it was overheating until something already went wrong and requires an expensive repair.