I've noticed a problem when importing Nikon Z9 RAW files into Lightroom. Importing directly from a CFExpress Type B card is much slower than expected.
To illustrate that this is not a problem with file size, I also shoot with a D850 (identical resolution) and have used it for years with no issue. Furthermore, I use a compressed RAW with the Z9, so the files are significantly smaller than what I'm used to (approximately 33MB/each vs 66MB/each).
To further illustrate that it seems to be a problem with Lightroom Classic's import, I've found a (pain-in-the-butt) workaround that completely negates the slow speed. If I drag the files straight from my card into a folder created for an event, then use Import->Add, Lightroom is extremely fast. The issue only arises when importing directly via Lightroom.
When using my workaround, a moderately full card (say 32GB of files) can be transferred and added to my LR catalog in approximately 4-5 minutes. This includes moving the files off the card into the new folder. When I attempt to do the same using the normal method of importing directly into LR, the process takes between one and two hours.
macOS 11.6.1
27" iMac Retina Late-2015
LR Classic 11.2
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