Exactly the same problem.
It starts when first entering Rivington and then it feels like a delay in loading resources for a new piece of the world.
But the problem does not exist on old saves - characters who reached Rivington before patch 4.
System specs:
Windows 11
AMD Ryzen 9 5900HS with Radeon Graphics
NVIDIA GeForce RTX 3060 Laptop GPU GDDR6 @ 6GB(192bits)
Driver GeForce Game Ready v.546.01 (10/31/2023)
Game version 4.1.1.3905231 (Steam)