The Argentine military has declined much more than the Royal Navy.
Their air force is now a joke, with many aircraft non-operational.
And while the British basically had no capability to shoot down Exocets in 1982, the Royal Navy now has hundreds of missiles on their ships with anti-ASCM capability.
The Argentines also have essentially no amphibious capability now.
Have a look at the HMS Dauntless diagram at my site, seems like this thing could shoot down any plane as soon as it leaves the tarmac.
I think the worst the Argentines would pull would be a blockade... it is doubtful they have any amphibious capability left, agreed. But the English are re-enforcing the area for a reason...