Mind you, my experience is all way pre-tinder. I've never been on Tinder, and things may work differently there, because if I understand correctly, you first need both people to already be interested in each other before you can send messages, and the messages are explicitly chat, so there a "Hey" might work. But on many traditional dating sites (many of which are scams now), you search profiles and send a message before you have a match, leading many women to get inundated with low-effort "Hey" messages from men with seemingly no content or personality at all.
Maybe the Tinder approach is better.