Well, things work until they don't. Predictions can only get you so far. See: new coke, qwikster, onlyfans trying to ban porn. But yeah I'm sure they did a cost benefit and decided it was worth

Yeah like how Blockbuster tested their plan to remain a brick and mortar store? Or Boeing testing their new jet design before they had two airliners crashing? Or Capcom designing SFV to be more like a PaaS and ultimately failing enough to let go one of their most veteran producers?

I think plenty of large big businesses make very stupid decisions all the time and the netflix account sharing thing honestly could’ve gone either way. Also, there’s no guarantee this is going to save netflix. They still have terrible habits of putting out garbage and canceling good shows that have plentiful viewership.

Netflix for the longest time has been trying to make lightning strike twice by treating every new Netflix original like it’s supposed to be the next Stranger Things. That’s a stupid thing to do. Of course I don’t give big businesses enough credit, they haven’t earned that reputation.

Wasn't there a news article floating around yesterday claiming that Netflix was about to ditch their cheapest ad-free option?

I suspect you are right, because Netflix is axing its lowest ad-free tier and those on it will either need to pay the higher ad-free or switch to ads.