I don’t think making work a form of play is feasible (perhaps easy is a better word) for most people, simply because of the nature of their job. Without some creative and exploratory aspect, it’s just menial, boring, devoid of any stimulation.
I am lucky enough that my work is such, but I got extremely lucky and basically made it my reality.
I think the way to look at it perhaps is that there is an element of challenge in play and an opportunity to win. So a job can be boring and menial but you have the opportunity to be the best in the world at what you're doing and you can treat every day as a challenge and opportunity at excellence, and in turn any job can be fun.
You could easily look at chess as menial, boring, and devoid of any stimulation but it's possible to find fun in that. Everyone should stop taking everything so seriously and challenge themselves to be the best.
I believe that I am the kind of person who can find something interesting in [nearly] everything, chess is interesting in that it is [functionally] infinitely and thus can be infinitely creative.
This creativity doesn't exist in Sisyphean tasks. It's one thing to say one must imagine Sisyphus was happy, and another to be Sisyphus, and be happy, or rather, to be content.
I am lucky enough that my work is such, but I got extremely lucky and basically made it my reality.