I've seen a lot of takes on sag joining the strike go by. Some focus on the fact that most actors are in fact not big names being paid big bucks so don't let the studios fool you. And yes very good, don't trust company propaganda.
Others talk about the less frequently mentioned (and more challenging) take that every actor, and writer too, deserves to be paid fairly for their work. Yes even if they are the big names who have already been paid bigger bucks. Excellent, love to see workers' solidarity and people learning the difference between well paid and hoarding money indiscriminately.
But the one I so far haven't seen mentioned, is the fact that you in fact want the big names with the big bucks there. You need them to join in. They add the weight, the leverage and are harder obstacles to ignore.
Sag and wga members are the army besieging the castle and the big names are the trebuchets ready to fuck shit up.