1. It's a function of cost. None of these things are cheap.

2. It might not be possible. Helicopters will need a somewhat direct line of sight to the container (which might be tucked in a cave), boats probably won't reach (too close to the rocks#, submarines... Lol.

The only viable approach is probably by land, which means months of construction work to bulldoze whatever obstacles there are... Which brings us back to point 1, cost

Economically impractical, yes.

You can bet that if for some reason the demand for those phones, or perhaps other things we may consider just waste today, rose high enough, there would be enough incentive to recover them.

Look up "low background steel" for one notable example. CFC refrigerants are another --- what used to be cheap and freely available gases were used in large quantities and simply released to the environment, then started causing environmental problems, so production was eventually banned and the price shot up enough that recovering and recycling became profitable.

"It's bad to release it into the environment" doesn't motivate as much as "it's very valuable so don't release it into the environment even if you don't care about pollution."

Yes it's physically possible to somehow retrieve and remove the container and phones. It would also likely be absurdly expensive to do so for the gain.

It's likely cheaper, easier, and safer to simply keep picking them up off the beach as they wash ashore.

Seems like they should be able to get a team of volunteers together to go to the shipping container and remove the phones by hand so they don't keep going out into the ocean. How hard can this possibly be?

Based on the description it sounds pretty dangerous for the limited value gained from doing so. The reporter said they could see the container, but that doesn't mean it's immediately accessible.

Can they seal the container?

Maybe, I don't have enough information to answer that. My guess is doing any work in a coastal cave that is only accessible at low tide is going to be expensive and dangerous.

It's reportedly in a cave accessible only at low tide. (I only have modest swift-water experience, but that's terrifying.) Of the three options you list, the only possibility would be a boat, and it's probable that the space is too restricted to get a large enough boat and equipment to move a shipping container in. And, it's a cave, so going in from the land side would probably require mining and still be dangerous.

If you just want to prevent Garfield pollution, it would seem like the best option would be to use explosives to close the cave and pretend it never happened.

It's more than the tide. They showed in the video that the container is deeply embedded into the rock and mud. It's not just a matter of walking into it and picking up the phones. Most of it is buried.

You seem to be one of the few people here who actually read the story to the end.

They literally walk up to the container in the video in the article, it doesn't seem to be difficult to access at low time (which happens at a predictable time twice a day...)

It is buried, not easy to retrieve... but you could just pour fast setting concrete on all the openings.