No argument, but none of that was on trial. They didn't lose because they largely ignore hate speech, misinformation, bots, etc - All of which are basically legal except in very specific contexts (licensed professional advice, incitement to violence). They lost because they lied about user privacy and their efforts at moderation.
This isn't apologia, but it's an important distinction to keep in mind. The first amendment is an effective defense of the content itself; it's not a defense against deceiving their customers and regulators. So why am I writing this? Because Zuck's appeal to 1A is merely another lie - Whether this stands or is eventually reduced on appeal, he's already spinning the PR away from the blunt fact of "we lost because lied", to the far squishier "Meh, moderation is hard, so sue us - Oh wait, you did LOL".