Besides these stories getting some traction, I feel that much doesn't come out of it, and often the "BigTechCo" doesn't even comment on the matter.
How will change happen? Are there organizations fighting this?
A public requirement for more transparent business practices may result from populations wanting to fight climate change. It's currently easy to release some data about emission reduction and how green a company is, when it's an estimation that nobody can reproduce (because access to the majority of the source data is privileged).
Regulatory punishment isn't realistic, because the companies involved are just massive and crucial for nations to even exist (e.g. petro-industry giants). Thus, only foreign companies get regulatory punishment.
The only lever here is a company not being able to do business without conforming to a certain base level of transparency. We already have nascent forms of transparency requirements in terms of non-proliferation of defense knowledge or equipment, some environmental laws and worker's rights requirements (e.g. child labor iirc).
But it will have to go much further in order for companies to be held to higher standards, to a degree that business intelligence is almost nonexistant and every customer can retrace the logistics chain of what they're consuming.
And that's sadly utopian, since any smaller company that publishes what contracts it has with which company (and is legally able to, due to new regulation) will not get new contracts, as long as there is competition that keeps silent.
If you’re referring to app platforms I think the answer is simple: Don’t build a business on another company’s platform if they have a terrible reputation and a history of screwing businesses like yours.
The other thing to consider with platforms is incentives. Platforms where your company doesn’t improve their bottom line won’t care about screwing you. So Shopify and their partners have mutual interests (both increasing shop’s profits), but Google doesn’t with its plugins and browser extensions. Facebook apps didn’t make Facebook more money so they had no problem getting rid of them and destroying businesses.