I think everyone struggles with this at a certain point in life and this extends beyond the tech sector.
Understanding the impact of your work is not always easy, but it is a necessity to feel like you are performing meaningful work.
What helps me is talking to customers and understand how our product makes their life better and what my role is in building the product.
Whether you are picking fruit, flipping burgers or building tech, you are a little cog in a system that hopefully produces a net positive to humanity.