Car manufacturers basically just don't give a peep, and just gather every single morsel of info they can get their hands on, and preferably sell that information to anyone interested.
So it's "worse than smartphones" in the sense that for smartphones, at least there are options that are privacy-friendly.
I tried to find the equivalent market share for privacy-friendly smartphones (and am undoubtedly not up on the latest trends there) to see if it was more or less than 0.02% of the market.
It looks like fairphone sells around 120K devices per year globally (out of around 1.4B total smartphone units). I realize that's not the only brand in the space.
(As an aside, the Fairphone by default comes with stock Android. It's primarily more privacy friendly in the sense that it is actively OK with running e.g. /e/OS on it as well.)
You may find it more challenging to leave your car at home while you go someplace like that. Sure, take Uber or public transit; that's all tracked too.
The article claims "more than even smart devices in our homes or the cell phones we take wherever we go", but doesn't elaborate on or substantiate the claim.