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
Net subscribers may have increased, but I suspect many of them have chosen a cheaper option. Since my family can no longer use my account there's no need to have 3 simultaneous streams. I chose for a cheaper subscription and expect many to do the same.
I guess they changed their minds then. Hypocrites or not I still feel like wanting to get paid for people using your service is reasonable. I've never used Netflix but if I did I'd imagine this wouldn't affect me much as a paying customer. It seems to mainly be an issue for those who either travel alot or are using somebody else's account