I'm actually not sure the Northridge earthquake was cited in the Richter scale, most references I see have it as about a 6.7, which based on the USGS catalog, was it's moment magnitude 6.7 Mw
https://earthquake.usgs.gov/earthquakes/eventpage/ci3144585/...
And today's earthquake for comparison:
https://earthquake.usgs.gov/earthquakes/eventpage/us6000qw60...
And some information of Magnitude types: https://www.usgs.gov/programs/earthquake-hazards/magnitude-t...
I think it's probably safe to assume, that today's earthquake is much more energetic at least.
yeah i misread the charts, where like 3.5ML (richter) is ~5.0, and i missed that it was mb rather than ML, 8.8 ~= 6.7ish body wave magnitude.
That's the thing with standards, there's so many to choose from.