I don't agree, whenever I take someones phone and start reading their private messages or browsing history, they always get nervous, even if I can't find anything.
People certainly care, even an average person is aware of problems with digital privacy and they would love to get it solved. But people care about a lot of things, global warming, homelessness, police brutality, they just don't organize well enough to fight those issues and fighting them alone is hard.
Also don't forget the amount of propaganda there is to live a certain way, to chase promotions on your job, earn more money and have a high social status. All of these things get in the way of deleting instagram,whatsup and etc.
There is also a problem with lack of marketing of alternatives, most people haven't heard of lemmy or XMPP chat.
I suggest we try to get people to start using these alternatives first, until there are enough users that they actually have a choice to choose either network and then a lot of people will delete mainstream apps. First step is to make it popular, second is to delete these bad apps. However even getting someone to use a new app is hard, since they are bombarded everyday to install some new app and are even financially motivated (with deals and discounts).
It is a hard battle, but a necessary one. Without privacy there is no democracy, voting is secret for a reason. We need a real democracy, where we choose laws directly, not by someone else we are forced to vote for due too lack of better choice. That requires safe and private digital communications. In person communication is very limited.