In Feb half term last year with my son, it was tied to boat on at one end (front, facing Rhosydd) and the pull cord had been left on the wrong side, presumably the last people found it easier to get out of the boat like that closer to the "shore". So when I pulled it, it was getting snagged on rocks about 1/3 or 1/4 the way back to Croesor.
I had actually stripped off to swim and putting harness back on for abseil down when I gave it one a last attempt with a hand jammer on the twisty rope (almost snapping it level of force) resigned at that point to my swim. To my surprise and even greater relief it came free! The water looks even colder surveyed while only wearing boxer shorts and a head torch. But I'd say if people aren't fully prepared to swim (or reverse back) then they shouldn't be down there. I think the canoe is great, it's a real bit of character so it'd be very sad for it to go, but it will end up causing rescue callouts of unlucky urbexers.