It still too soon to tell honestly. The major bump of this policy is a one time surge of all the built up password-sharers but it's likely not going to be huge swing to their growth long term.

And then these new subscribers, are they going to stick around? A common scenario might be someone cutoff midway through a series just subscribing for a couple months to finish them off.

And for the same reason I would expect new subs from the policy would happen quickly while unsubs might be delayed. The main account holders would likely finish off their series and take time deciding on their new streaming service before outright cancelling.

And all of this just ruffles feathers and makes the service a bit less valuable right when real competition is heating up.