Now measure how many non-SWE jobs are pointless. And keep in mind Price's law potentially applying, where half the work is done by the square root of the number of people. Then measure human activities of any kind, not just jobs.
You can conclude that it's all or almost all pointless, but really points and meaning are made by individuals. They exist, just not "out there" like electricity, only within brains. So for yourself it's mostly just a perspective issue. Even among people who 'cope', the same job and work can feel one way or the other at different times, when it feels one way there's really no coping involved.
Maybe try taking something that gives you a close feedback loop with paying customers -- that is, you yourself talk to them, there's a direct connection between your work and its effects on them, even if you're not the Decider or whatever for overall business goals. When you see how happy they can be about paying for your stuff (even stuff you think is kinda meh), it's less about "squeezing" them, and more about keeping them happy, seeing them happier when their additional needs are listened to, and continuing to deliver value in mutual exchange. This isn't a sure thing to change your perspective and your gigs may have been that close anyway, but I find it helpful to have that context rather than something super far removed. (Though even then if you trace some lines out you can find meaning in your own cog -- try doing it in reverse, too, consider some brass on some trivial object near you like a doorknob or a pencil wrapping below the eraser. Where was that brass made? Where was the iron and zinc mined from? What were the miners' tools made out of, how were they made? How was it transported to its present location? There were lots of people with jobs small or large involved in every thing around you.)
Job length has a quality of its own, too. 6 months is often not enough time to really see the fruits of your labor. It's an interesting feeling to build something collaboratively and incrementally over longer periods (one year, three years...) with early adoption at first and lots of limitations or problems and broader adoption later with more flexibility and fewer problems.