The expectations you do not know you have control your happiness more than you know. High expectations that you currently have don't look like high expectations from the inside, they just look like how the world is/would be.
But "lower your expectations" can often be almost useless advice, kind of like "do the right thing".
Trying to incorporate "lower expectations" often amounts to "be sad". How low should you go? It's not clear at all if you're using territory-free un-asymmetric simple rules like "lower". Like any other attempt at truth-finding, it is not