Speaking as someone who also has a fear of swimming pools - I felt for that lad as he went into the water, his dad is a bully. Hardly the way to help him get over his fear of water. pudding.
I think the kid seems serious enough that he doesn't want to go in the water regardless of how deep his fear goes. If someone did something like that to me, (throw a wasp/spider/some other hideous thing I'm afraid of) you could be pretty sure the chair wouldn't miss the head...
China - if he was that scared of drowning, he wouldn't need to be asked / tgold to get out of the pool, nor would he swim to the side as he did - an obviously competent swimmer, and he wouldn't be allowing himself to duck under the water like he did without a deal more noise and splashing than that.
Plus the videoing brother makes no comment when chairs are slung into the pool?
It's all silly nonsense, don't stress yourself over its reality - there is none.