Positive consequences as a result of your actions. These can linger and affect life on earth long after your passing. A possible outcome or consequence of something you did or did not do might be an integral event in a chain of actions for better or worse. It's mind boggling to try to imagine how deep this can get.
If anything, it ought to inspire responsibility and thoughfulness.
I still think it's important to joke, be light hearted and simplistic though. It's just a nice thought to keep in the back of ones head as a reminder as to just how much impact one life can have in the grand scheme of things, because the opposite view seems to be prevailing for the most part, i.e "I'm just a grain of sand in the desert that is the universe" or similar defeatist attitudes.
To make another person feel appreciated, valuable and loved is, I think, the greatest work one can do. Anything else is worthless unless tied up with this higher purpose. Writing a book, learning a skill, constructing something... anything really is worthless in the grand scheme of things unless it reproduces positivity, love or constructivity in others. The internet is a great opportunity for autistic people to accomplish this, since we are not good in real-life interaction.
I don't mean to imply that there is no value to something you do in solitude, that nobody knows of. Just that it's worthless after your passing and only carries with it worth and purpose within your own consciousness.
That's perfectly fine from a microcosmic perspective.
But when you start thinking about the fact that your time here is limited, then the prospect of leaving a legacy of positivity, no matter how small or seemingly insignificant, can bring purpose to someone elses life. Then even miniscule actions can have monumental meaning in the grand scheme of things.