It's pretty hard to compare audiences from the '80s when there were only a handful of channels making primetime content to now when you have content on demand from dozens of sources at all times. For a new show on network television, ~7 million viewers is pretty substantial, and a 1.0 rating in 18-49 makes it one of the most successful shows in that (lucrative) demographic currently airing on television.

I mean it's still impressive given that the original aired before streaming and there were probably less than half the amount of channels outside of streaming.