Is it better to use two sticks of RAM in two slots instead of four?

Yes, two sticks in two slots is the sweet spot for most systems. Running 2x8GB in a two-slot motherboard gives you dual-channel memory just like 4x4GB, with no performance difference. Two sticks are easier for the memory controller to handle, especially on Ryzen builds, and improve airflow around the CPU cooler. The only downside is no room to upgrade later without replacing both sticks, but if 16GB is enough now, that’s a problem for Future You.