Why do white-collar employees believe they are more valuable than the production workers who are actually taking part in making the end-product?

Kind of a silly disagreement.
Neither would exist without the other.

I didn’t realize such issues were going on in Tesla

Yea
I’d say production workers are more essential than office workers in general
But everyone contributes something and I don’t disrespect anyone for their job

I worked in an old fashioned production line company making electric can-openers, electric engraving tools, bug sprayers etc. for name brand companies. The biggest contract was for assembling appliances for a major name brand.

The white-collar office workers maintained that contract and re-negotiated it every time it expired. Eventually we lost it to a Chinese enterprise. The office switched to finding new contracts, 75 production workers were let go. They were too expensive to compete with Chinese slave labor.

Who was more valuable?

Corporations have a slave-owner mentality

Ego

Because we're in a capitalist thinking system as well as a capitalist economic system. They probably don't think very much.