No they aren't? He's trying to save himself from losing billions more dollars. It has nothing to do with free speech. As the other poster stated, it's about perceived IP theft.
Assuming 'we' is lemmy, Musks motivation is complete different, aka money. You restating the point you tried to make doesn't give it any more credence.
Premise 1: Fighting the enemy of a person, group, or thing can be a way of protecting that person, group, or thing.
Premise 2: Meta is an enemy of free speech.
Conclusion 1: Fighting Meta can be a way to protect free speech.
( P1 + P2 => C1 )
Premise 3: When a specific action can be used as a way of creating a specific outcome, we can say that that action is consistent with having the goal of creating that outcome.
Conclusion 2: Fighting Meta is consistent with having the goal of protecting free speech.
( C1 + P3 => C2 )
Premise 4: Initiating a lawsuit against X is a way of fighting X.
Conclusion 3: Anyone engaged in a lawsuit with Meta is undertaking actions consistent with having the goal o protecting free speech.
( C2 + P4 => C3 )
Premise 5: Elon Musk is engaged in a lawsuit with Meta.
Conclusion 4: Elon Musk is behaving in a way consistent with having the goal of protecting free speech.
( C3 + P5 => C4 )
QED
Now, I you can take this argument down by knocking out any of the premises. It relies on all five premises. You can also disagree with the logical conclusions.
I would be curious to know what you think is the weakest of those premises.