"Be cheerful. Strive to be happy."
Given the context, it seems to me, this directive is aimed at you and I, the readers. The mandate is one of personal responsibility. It's not saying, expect someone to do it for you. It's not saying hold someone else accountable for your lack of happiness. It is suggesting that you be "cheerful" and that being happy, is going to require your participation. I don't say effort, as I would suggest, it shouldn't be forced. But that choice does come into play.
I would say, I'm generally pretty happy. Not giddy, not deliriously happy, all day, every day (in fact seldom, if ever). More like, I have developed the ability to enjoy my own company when called for, and I try to be a positive presence, when in the company of others. I actively aim to expand the qualities of acceptance and contentment.
It doesn't mean I don't get angry or agitated at times; but I'm not waiting on a particular set of circumstances to arrive, in order to then, be happy.
Naturally there would be those, that have been in my life at one time or another, that may have witnessed or been on the receiving end, of more than their share of my unhappiness, and they would possibly spin a different perspective.
Conversely the manager of the Harley motorcycle service department shared with me, that he was talking to someone else in the department about my bike - his assessment was, "he's a pleasure to deal with, always comes in with a smile on his face...." I was genuinely surprised to receive this feedback - not that I thought I was "unpleasant," but it was nice to hear. I guess in that environment, (working on motorcycles) and Harley's at that (expensive when it comes to parts etc.) the staff have the dubious responsibility, to not always impart happy news to their clients. My demeanour is not contrived to win me special favours - but I believe I get great service out there. I do my best to treat people respectfully.
Of course there are times when I fit squarely into the "surly to bed - surly to rise" club. I try to avoid interacting with people while in this state if possible.
I don't believe it's any more or less unrealistic to be as happy as I can (despite the world events) than to be chronically unhappy. The former isn't indicative of being in denial and the latter doesn't imply I'm any more sensitive or caring. Challenges of day to day life certainly won't be more readily overcome by being miserable about it. If anything that's more apt to bring you down.
Bobby MeFerrin gave us: "Don't Worry, Be Happy!" (Sage advice - I'd say!)