That's only partially true. When you only have one corporations interests, things get shady very quickly. When you have multiple, competing corporations, they have a vested interest in keeping their competitors honest. It would be very rare indeed to find something that every company wanted to downplay at the same time.

Spectre and meltdown are a great example of this. Sure, ARM, Intel, and (to a lesser extent) AMD may want to downplay these things, but Google did not, so it became a big deal anyway.