Two things: Control in your use case is much more limited by turning on full ray tracing than PCIE bandwidth, and secondly, well, even though 8 lanes on PCIE 3.0 seems a bit low by today's standards, it only becomes a really huge problem for your GPU when you run out of VRAM. Which on 1440p, with a 16GB model, isn't going to happen with Control. Or most other games at the moment. If any at all.
If you had an RTX 5060 (TI) or a RX 9060 XT with 8GB, then, well, the card would probably crap itself, even on PCIE 3.0 x16. Well, maybe not in Control, IIRC it just starts dropping texture quality or entire textures when VRAM gets low, but for games like Veilguard the 1% lows just drop by over 50%.