It is kinda big, previously you had to send the host unencrypted to support SNI which in turn was needed to support https for multiple sites per one IP address, which was needed because we lack IP addresses. So there were basically two options: compromise privacy a tiny bit (by sending host unencrypted), or make it impossible for most websites to have any privacy at all (by making it impossible to have a https certificate).

Now you can have the best of both worlds. Granted, you need to have DoH (which still isn’t the default on most systems AFAIK), but it’s still a step in the right direction.