While I agree that there are a lot of Trump backers who are easily duped, or quick to pass on a meme/email/conspiracy, the same is true of those who are not backers of Trump. Maybe not to the same degree, mind you, but there are many people who feel more comfortable making quick and easy statements that sound important/intelligent.
It's much easier to surround yourself with similar minded thoughts, so you don't have to run the risk of finding out you were wrong. And if someone else then tells you that you are wrong, it's difficult to take that new information from outside of your bubble. So people will double down on their belief systems.
Everyone can point out examples of the "other side" doing it, and use that as proof their side doesn't. Hell, I kind of did in this very post.
Stupid people are just that, stupid people. If people want to take it as a slight against Trump voters, and they're a Trump supporter, that's on them.
I hate people falling for stupid shit regardless of their political/religious affiliation.