RIP. I'm not sure if it's disrespectful to be saying this but let's not make his death go to waste.

Swimming in swimming pool and swimming in the sea is 2 different thing altogether.

I've heard before that in a high wave seas, even professional swimmer might find it a struggle to swim much less to rescue another person

Even if you manage to swim to the drowning victim, you need to have plan of action on what you need to do. You cant just swim straight to the panic victim as their natural instinct is to pull whatever they can reach to let them stay above water, remember Titanic and the scene of Rose with life jacket swimming near drowning victim?

If they can't calm down, you don't go near them. I've seen lifeguard knock out a drowning man to save his ass (on tv)

Malaysia songlap country, no money to hire life guard, seldom go to beach and see life guard

Do not underestimate the sea wave, when looking from the beach, all you see is a calm sea, but it is different after 50-100 meter into the sea, even a 1meter high wave might look like a small ripple from the beach

You cannot use the normal frog, butterfly, breast stroke, freestyle on the open sea, notice in Baywatch how the lifeguard 'dive' into the wave every time there is an oncoming high wave crash? I'm not expert but I'm sure that's how you're suppose to swim