Wordpress site has a lot of connections
5 Connections/sec is slightly high.
5K QPS is high.
Max_used_connections is already very high.  Part of this could be due to nothing being cached in the buffer_pool after the restart, which was barely an hour ago.  What is Max_connections?
Aborted_connects/sec is quite high -- which is what you are asking about.  On the other hand, Aborted_connects/Connections is moderately high.  Any chance a hacker is trying to get in?
If some of those 'slow' queries run a long time and/or block other actions, that could explain some of the issues.  What is long_query_time?  (It defaults to a virtually-useless 10 seconds; change it to 1.)  Are the slow queries being logged?  300% CPU usually indicates inefficient queries (indexing, formulation, etc)


Recommendations:


Turn on the slowlog.
Run for several hours before analyzing.
Digest the slowlog to see what is naughtiest.
See which of these you would like to pursue:  http://mysql.rjweb.org/doc.php/mysql_analysis