Is it still the case that if you follow someone and they DM you but if they're not following you, you cannot send a DM back? Seems like it should always be the

Is it still the case that if you follow someone and they DM you but if they're not following you, you cannot send a DM back? Seems like it should always be the case where if someone initiates a DM with you, you can respond even if they're not following you since they've implicitly granted permission for the communication by reaching out first.