Revert "MM-49485: Set BoardsProduct FF to on by default (#22006)" (#22075)

This reverts commit d27d7bc8f7.

model/feature_flags.go

@@ -95,7 +95,7 @@ func (f *FeatureFlags) SetDefaults() {
 	f.InsightsEnabled = true
 	f.CommandPalette = false
 	f.CallsEnabled = true
-	f.BoardsProduct = true
+	f.BoardsProduct = false
 	f.SendWelcomePost = true
 	f.PostPriority = true
 	f.PeopleProduct = false