Because it's an applicance. Are you downloading donky kong? Twitter? What new software features do you think the manufactures are going to give to you?So? That's kinda the whole idea. And as Fightnfire stated, it can be used for good as well. I'd love it if mine could be updated to use Android Auto for example. Or even update the Bluetooth.
Why can't it be more? The funny part, that's what people said about cell phones in the early days. "They're just appliances, they just need to make calls." That changed and I think for the better. So why can't the vehicles be able to download new features as they come out?
What have we seen to date? GM selling your data to insurance companies and them charging you for "hard accelerations" lol, Toyota and BMW selling you subscription services like remote start. And of course the kill switch which is coming. You can look forward to that future all you like but I suspect you're just arguing now for the sake of it.
Google can turn off my truck or sell my data to insurance companies?That ship has pretty much sailed. The damn grocery stores have more data on us than these trucks. And we won't even talk about Google or any of the social media outlets.
I think you are being a bit too paranoid about it. Believe it or not, in today's world, it's so much better than it was. I remember when my SSN was printed in the local newspaper. Can harm be done with our trucks Tx/Rx'ng? Of course, but will it? It's like keyless entry. Can a hacker snatch the signal to use it to steal my car later? Sure, but I am more than willing to take that chance in trade for convenience.
There is no convenience, only downsides. As I said, map updates (which at this point is the only real conceivable upgrades that you would get on a car/truck) can easily be applied when you're getting it serviced for other reasons.