Plenty of systems run without a dedicated graphics card, using the built-in iGPU available on Intel processors. If you drill into some of the systems here:
Blue Iris Update Helper you can see how many are using Intel acceleration (that's the iGPU) and the instances where people might be running with dedicated NVIDIA graphics cards.
I feel like most those cases, the person either already has a powerful workstation, and it pulls double duty as a
Blue Iris computer, or maybe it was the only way to support the number of cameras they had installed at the time (to offload some cameras to GPU to reduce overall CPU usage and support more cameras).
