As seen above, the only way to select them is to click and drag. I can’t click to select. I’ve had this issue in the past (before bulk importing was added) but I haven’t found any pattern as to why it happens.
Apologies if this is a known issue, but it certainly causes issues when working on areas where click+drag will select lots of unwanted parts.
When I resized the meshes the issue resolved itself. Perhaps it was because I imported the models without having them scaled down so they were incredibly large.