I'm not even quite convinced they can't grasp the concept. People think they 'own' their digital copy of The Rescuers Down Under, when technically they've leased it. They generally understand they shouldn't post their credit card numbers online. I think it's more likely that they just don't understand the consequences, and even if they did, generally feel dis-empowered to do anything about it. That's a dynamic that has existed since before the internet.
I think most people would agree that if you take a photo of someone who agrees to you taking it, you own the rights to that photo. But if a company collects data about someone voluntarily using that company's product, the person owns that data? I don't understand where the line is drawn.
For example, if I own a book then I can read it, doodle on it, or lend it out at any time. I can't prevent other people from reading/defacing/whatever their copies of the book.
why not treat data the same way ?
yes it will be very disruptive to some businesses. i hope.
Like most people here I'm fairly hard line when it comes to personal data abuses but I still struggle with the concepts of owning data about yourself. It's a confusion I see amongst less technically literate people when a well meaning person explains to them the importance of some latest data breach and they try to understand the concept that they owned this data, it was theirs but now it has been "stolen" or abused in some way.
I would consider going as far to say that framing the data as owned by you is a bad approach, but maybe I'm just being pedantic about the language. Company A does have data about me, but I don't own it, and they have responsibilities to protect it (or delete it if requested), but I don't see any ownership in the equation, especially when the nature of the data can become quite abstract while still maintaining some reference to you.
Not to take away from the intention or sentiment of framing it that way though, I'm just musing.