"The EDD says it is working to verify the identities of people who made claims and many remain under investigation"

It's identity fraud. (Entirely because of the tragic state of US [and global] privacy and state-citizen communication culture.)

It's not people taking advantage of welfare and deciding to not look for work. It's career criminals.

I agree that it's career criminals, many of whom are even overseas. The problem is that these agencies have to be able to distinguish legitimate vs. fraudulent claims, and sometimes the processes they come up for doing this could be described as "jumping through hoops."

How does that compare to other years, both in total amount of fraud and in what percent of total paid out was for fraudulent claims?

If the system is fine except in situations like a once a century global pandemic that throws way more people out of work than normally happens even in most recessions and throws them out of work for longer than is normal where it jumps to a fraud rate of 30% or so (and presumably returns to normal when the pandemic is over), I'm OK with that.