To some extent that's true, but generally the US intelligence does its best to keep the secrets that it gains from its allies under wraps. The free exchange of intelligence between Britain and the US has been a cornerstone of the Atlantic Alliance since WWII, and Britain has every right to be furious that classified information it exchanged with partnering agencies in the US ended up on the front page of newspapers on both sides of the Atlantic.
This wasn't strategic leaking of information. This wasn't some scheme to use classified information to gain some advantage. It was just the big mouths that currently run the Administration spouting off because they're a band of irresponsible children. Like Trump blabbing off about Israeli intelligence, this is going to have ramifications, both for information sharing between the US and its allies, and likely between the White House and the three letter agencies. It's becoming crystal clear that the current Administration cannot be trusted with classified information, and Congress and the three letter agencies are probably simply going to start withholding information, both to preserve active operations, and to preserve critical foreign alliances that the Trump Administration is putting at risk.