If you want all queries to only use one processor, why not pull the other 23 out? That's essentially what you've done by setting maxdop to 1. It is NOT a good thing to do.

Of course you won't see any CXPacket waits with maxdop at 1. Maxdop of 1 means never parallel.

Maxdop should probably be changed from the default, but not to 1. See the last section here: https://www.simple-talk.com/sql/database-administration/gail-shaws-sql-server-howlers/

CXPacket waits are not an indication of poor performance. They're an indication that queries are running in parallel. That is all. If you have lots and lots and lots of CXPacket, then, to reduce them and improve performance, you need to look for the other waits. In any query that's got huge CXPacket waits, there will be one or more threads that have some other wait type. That's the wait type that you need to investigate and resolve.

Look for the other wait types

Optimiser your queries

Increase cost threshold for parallelism

Set maxdop back to something > 1