To tea or not to tea....

[Nevadaref]

For the OP:
That conversation with the coach was way too long and involved. Even during FT attempts officials have players to watch.
Coaches who are pricks don’t deserve any interaction or explanations.
If you say anything at all, keep it to only a few words. Eg I had a good look.
During FT attempts, move 8 feet out onto the floor and ignore the coach.
If the coach behaves inappropriately, issue a warning or technical as necessary.