Sorry for the choice words, but shit like this makes my blood boil. You're not trying to "keep our children safe" motherfucker, and you know it. You're trying to prevent people from being able to have private conversations, so your secret agencies can harvest all the data from everyone easily. To phrase it as "but think of the children" is instrumentalizing the actual victims of child abuse and you should be ashamed.
To be honest the motivation to keep our children (or people more generally) safe seems way more clear to me that the motivation… to prevent people from having private conversations… to what end?
To expand the total surveillance even further? It seems to me that every government, no matter how liberal or progressive, loves surveillance. Look at how quick European governments started to vacuum up the data from mobile operators when COVID broke out - all "for your safety", of course.