These are 0, 30 and 60 degree graphs. Seems to pretty closely follow the standard pattern to me. Not sure what causes the big dip at 15k way off axis, but i don't think a dip at 15k and 60 degrees is a problem for you in a car.
If you're really into this and really want to learn about speakers and how they work, I suggest "High Performance Loudspeakers" by Martin Colloms. It's excellent and it's a bit easier to read than some of the really hardcore explanations.
Here's a used copy for $4.This will be a better use of your time than reading here or in FB SQ groups.
High Performance Loudspeakers by Colloms, Martin: Good (1997) 5th Edition. | Better World Books