As someone on a different side of the fence (not an anti vaxxer, but someone whos not going to be taking the Covid shot) I have similar overall sentiments about much of the anti-anti vaccine rhetoric. Some of it is straight out of 1940s Germany and not just from Jim on your Facebook feed. Prominent politicians referencing anyone who hasn't taken the treatment as being dangerous or diseased. Low people who you wouldn't want near you. Thats before we've even gotten near mandates.I think soc presents a tolerable individual argument unlike the total rubbish I'm used to hearing.
True anti-vaxxers are a lost cause. They have a deep level of distrust in government and institutions. It means you can't cite numbers or facts because they think they are made up. In my experience they are also on board with every notable conspiracy theory of the last 100 years. They don't just like that album, the whole catalog is superb.
They also do their own research which should be applauded but unfortunately they draw conclusions on evidence that they don't even understand. The 'sheep' listen to the doctors while they make an informed choice from a dubious pre-print scientific article (Which is highly ironic considering their distrust of science).
Gave it some thought this year and decided to just stop arguing with them. Neither party gains anything from it.
I've come to the same conclusion as you though. Its absolutely not worth engaging in the conversation 99% of the time. Which is a shame given the magnitude of what's going on right now.