That's not a "teardrop". Are people actually calling it that?

Also, two phones does not make a standard. Even the Mate 20 Pro has an iPhone-style notch.

Both have the slanted sides that I think "passes for" teardrop shaped, although it's clearly more slanted on the OnePlus.

And indeed I was referring to the Mate 20 and Mate 20X rather than the Pro.