Confused by PCIE ! Is my 'budget' AlderLake 6500XT build okay?

Only double-width full-height, full-length GPUs are supported in the 3-slot PCIe expansion cage Figure 1 Numbering

Or is it only devices connected to PCIe-3 slot that would impact speed of the PCIe-1 slot Thats how my GPU runs as I have 4 NVMe drives

pcie expansion slot 4 lanes 4 of them are used to connect to the chipset So 20 lanes are available for direct connection 16x goes to PCIe Slot1

pcie 30 x4 slot PCIe Gen 4 is the latest and fastest PCIe standard available on motherboards and compatible CPUs PCIe Gen 4 cards can accommodate the full bandwidth that