Though, if you dig down, even these "think of the children" people usually have strong ties to government.
I'm not going into that now though. #chatcontrol
Examining it further, while "WeProtect" appears to have a "company or two", currently featuring Snapchat, this doesn't seem like much more than a token company to make the org appear more diverse than it actually is. The "foundation" is overwhelmingly in the hands of governmental / law enforcement interests, as is it's direction.
Also, these companies aren't exactly ones known for being protective of fundamental rights, such as the freedom of expression and privacy. Snapchat has never used E2EE, and hasn't been known for making difficult policy decisions, or opposing rights violations. If anything, it seems they're more preoccupied with trying to wipe their reputation away of being a "platform used primarily for sexting".
Google / Facebook, if they're still there, might balk at breaking E2EE. However, it's not clear this might have been discussed with them here, and this is not the only way someone's rights might be violated. They also don't have a unique interest in effectively advocating for someone's rights. Even if they did, their presence seems mainly advisory.
https://www.weprotect.org/wp-content/uploads/WePROTECT-Advisory-Board-Terms-of-Reference.pdf
"by advising the steering committee of the new Global Fund to End Violence Against Children and helping to secure funding for the Fund’s work"
This refers to one of the roles of the Board.
Interesting... It never occurred to me they might be getting funded by these people.