Poe's law is a thing, and assuming that everyone is joking when there is NO indication of a joke (especially in a medium that cannot convey tone without lOoKiNg LiKe YoU'rE hAvInG a StRoKe) makes the internet a worse place for actual discussion. Use basic internet hygiene, and remember to close your sarcasm HTML tag, using the following code as an example:

I'm sure glad that everyone is kind on the internet, and they don't call others stupid for making the assumption that someone is being genuine!

Or the following method, which works when you need to mark the entire as sarcastic:

I'm sure glad that everyone is kind on the internet and they don't call others stupid for making the assumption that someone is being genuine! /s