Model importing take too much time to display in viewport

Yeah, as @yaustar says, that model is huuuuuuuuuuge:

image

1M vertices and 1.8M triangles!

It looks like you obtained this model from CGTrader? Typically, a model like this would be used for doing renders (i.e. not for realtime rendering!).

We use a similar model for our BMW i8 app:

But we assigned a 3D artist to poly reduce the model to something a lot more sensible - a little over 100K triangles if I remember right.

Another suggestion for you is to see if all the data in that model is required. For example, do you need the second UV set?