Context and application is everything.

WD40 has grown to include countless other products. But in our case, I believe the thread was about the original "WD40 - Multi-Use Product".

WD40 is a lubricant... but only under specific use cases. Would you use gear oil in an engine? Gear oil is a lubricant. Engines need lubricant. Again, context and application.

At most, WD40 Multi-Use is a short-term lubricant, which is perfect for loosening up crusty hinges, tools, and such. Would you use motor oil to dislodge a stuck lug nut?

In electric fan application, WD40 can help loosen up the sleeve bearings if it's really dried up and stuck. This can prevent scouring the brass sleeves when disassembling the rotor. But it needs a more permanent lubrication designed for the particular interface during assembly.

I think it's unfair to vilify WD40 if you have misconceptions about its usage.