This problem has existed for many years, but it still hasn't been fixed. If I create a project not with 10-15 files, but if it's about a wedding or some corporate event, I have to import 200-300 files from each camera into the project, and that's when real problems with previewing in the Bin begin. It takes an incredibly long time, and all productivity is reduced to zero.
And this doesn't depend on the equipment I'm working on, as it is far from being weak.
My configuration:
CPU: i9 13900k
RAM: DDR5 6000Mhz - 64GB
GRAPHIC CARD: RTX 4070Ti - 12GB
All files on SSD and NVME
I will attach a video so you can see how slowly the previews are generated in the Bin