I get more spam email than legitimate email

Email used to be useful. Now it’s annoying.  It was used for checking on clients and communicating with them.  Now more spam hits my many email boxes than ever before.  Most are about getting business loans and improving my web sites. The rest are various other things.  One thing I do to reduce them is invoke a Global spam filter for all my email accounts on each domain.  I can filter by many categories but I usually use the “Sent by” field.  Typically I filter by the domain of the sender so all email from the domain gets rejected.