Assume that it takes 5 minute to connect a bridle to a container, hook it to a helicopter, and move it...and then also assume that the helicopters can run 24/7 and never have to refuel, that they can hot swap in pilots, and that there is never a single problem, you're talking about 25000 minutes, or about 17 days of absolutely non stop running helicopters.
And that only gets you 1/4 of the containers, and it might not even work at all.
(It's not a dumb question, and I'm sure that it was already discussed by the team who is dealing with this. It's just that the scale of what is happening here is restrictive.)
Amount of actual containers is probably the 20.000 divided by 1.6 or so, though it's not a given that any vessel is fully loaded to max capacity. Sometimes need to deal with restrictions.
Those heavy ones would be evenly distributed in the bottom of the hold, down below the water line. Low-weight ones are on top, for ship stability.
It appears to be roughly 7 x 20 x 25 containers, or 3500... (height x width x length.)
EDIT: Freezing this video I got a better view of how it's stacked today. I'm sure this is imperfect, like I said trying to count candy in a jar. But I'm curious what the real number of containers is!
H X W X L
10 X 23 X 25 ~= 5750
https://www.reuters.com/article/us-egypt-suezcanal-ship/beac...
That said, taking off some containers is a viable option but it'll probably have to wait for a crane ship to arrive.
Hooking them up to a helicopter would be a slow, dangerous process as well.
Weight-wise, the average container could be lifted with a military heavy lift helicopter: The ship carries 20,000 tons, i.e. 1 ton per TEU, and a CH-47F can lift 11 tons. Although a TEU can weigh up to 26 tons, so you couldn't lift the heaviest ones.
The problem is speed: A ship-to-shore crane at a properly equipped port can do a lift every 2 minutes. Ports can speed things up by lifting several TEUs in a single lift - but you'd also expect a helicopter to be slower, because we haven't put decades of optimisation into the process. So let's assume those cancel each other out.
If they can keep up that rate with a helicopter, and they operate 24 hours a day, it would take 28 days to unload the ship.
I suppose it's possible you could find a bunch of pilots confident in cargo handling, landing on ships, and close formation flight all at once. Or that the ship is large enough the helicopters would practically be independent of one another?
Each helicopter has a crew of 4 on the boat and 4 on the shore. They hook 4 chains to the 4 corner hoists of each container. Say it takes 1 minutes per container to affix the chains, 1 minute to fly to the sand, 1 minute to unhitch, and 1 minute to fly back. Thats a lot slower than agricultural helicopters, but nobody will be very practiced with this yet, so it'll be slower.
The entire ship could be unloaded with this method in 5.5 days. Perhaps less if not all the cargo needs unloading.
The job could be half done by now...
It takes a purpose built crane a few minutes to unload a container, so I sort of doubt a helicopter could make it happen faster.
Although I suspect you don't want to repeat that trick too many times without serious inspection/maintenance.