Isn't there is a slight difference - the maximum expected Japanese earthquake (9.0) magnitude is much more powerful than the maximum expected California earthqu

Isn't there is a slight difference - the maximum expected Japanese earthquake (9.0) magnitude is much more powerful than the maximum expected California earthquake along the Calaveras/San Andreas (8.0)? Cascadia looks to be another 9.0 fault line but the epicenter would be closer to Seattle/Portland than California.