If you have a low-traffic node, you're doing two things: 1) Lending liquidity to the network at a very low interest rate, and 2) Placing your bitcoin on a self-hosted platform you can securely send small payments for a very low fee. The value of (1) may be low, but to the individual the value of (2) may be high such that it significantly reduces risk and fees compared to utilizing third party platforms. To me (2) is the primary reason for running my own node. The more my node becomes optimized on the network, and the more the network becomes utilized in a widespread manner, there is a chance that the profitability of (1) increases but that happening per-chance is turning out to be more unlikely than not.