I’m not sure that there needs to be a any grand cosmic reason for life to exist. Life could just be an accident of random events in our little corner of the universe.
Natural selection offers an explanation for how life changes across generations in response to challenges in the environment. It does not require a plan, just that the outcome of a chaotic process (reproduction) creates mutations that produce a slight edge, or at least no reduction in reproductive efficiency.
Not a big gamer, myself, but it seems like Valve has done a lot of work to make many (most?) Steam games run well under Linux.
Drivers have come a long way, and a lot of things just work, but it can definitely depend on what hardware is in your system.