Trustd running high CPU and system.keychain

I've tried all the suggestions on here to stop Trustd constantly running. Nothing works.

But when I tried deleting the system keychain to see if it would help, something weird occurred.

When I restarted, expecting to have to enter my wifi password, it connected as if I hadn't deleted the keychain at all!

'getinfo' shows the new keychain was created today, but 'keychain app' shows everything still there from before...all passwords, wifi passwords, etc.

Can you explain this? How can everything still be there if I deleted it?

It might explain why I'm still having trustd issues as nothing has changed to see if this might be the issue.

Can you suggest something?