I haven't watched much of John Oliver show, as often I find his brand of humour too laboured and over the top. However, every time I have watched there are a few laugh out loud lines that are set up very well. The crypto one and recent one on Brett Kavanagh were worth watching, and he actually makes plenty of valid points in these

As for it being 'propaganda', anyone with an agenda can fall into that charge. Fox News or more extreme Info Wars are far worse for this (and pretty humourless unless you're laughing at them!) Sure JO's left leaning, but the creators of the show simply understand their target market. Poking fun at that which you don't agree is a very old tradition, so I wouldn't get too upset about it.