I don't know if I'd go so far as to say it's by design, but I definitely share your observation that capitalism doesn't leave much time and energy you would need to pursue hobbies, and it's way easier to get a dopamine high by consuming.

Even if this phenomenon is not by design, it is definitely synergizing very well with capitalism, and therefore there are people who exploit it and, in turn, support capitalism with their actions.

It is actually a depressing example of Niklas Luhmann's systems theory, which states that every system inherently tends to stabilize itself.