Probably all approaches are needed.

I'm simply stating, that if no one is on the inside, then we're missing out on a possible interaction channel that could help changing FB.

Simply trying to get in to be on the inside - without lying, is better than not even trying.

Of course, trying to advocate for better political control (privacy, transparency, lower barriers to enter the market) is important, and can and should be done while trying to engage with FB, trying to get close to their internal decision making process.

And, naturally, not everyone has the affinity to work at FB, but since it's a spectrum, likely there are a lot of software engineers that do have some ethical concern with regards to what and how FB does, and they shouldn't be discouraged from working at FB, but they should be very much empowered to be able to stand up and leave when their moral compass signals.