Oooof almost a good meme.
Shrek 4 was released on in 2 July 2010 in the UK. The Tories had won the general election by then and formed a coalition with the Lib Dems.
How can we trust you?
Well tbf, in some cases, factually incorrect memes are a way to quickly spread misinformation and can definitely be bad for that reason.
I think the original commenter was at least somewhat joking in this particular instance, though. “How can we trust you?” seems like an odd thing to seriously ask a shitposter. I could be wrong, tone is hard to read online.