Can Lightroom be adapted to an offline workflow?

I've used Lightroom Classic for a number of years to manage my photo library, and it works reasonably well. However, I've noted that the new version of Lightroom runs much faster and overall feels nicer to use to me, so it would be nice to migrate to it.

I'm running into some issues using it for a non-cloud based workflow though. I realize that it's mainly developed with cloud storage in mind, but I had assumed it would at least be possible to use it with locally stored photos only even though some features might be missing.

Currently, I have a smaller system drive (where Windows and Lightroom are installed), and a larger secondary hard drive that contains my photos occupying about 1TB.

In Lightroom Classic, I can simply import those photos to my library, they will remain in place, and it all works without issues. In Lightroom, if I attempt to do the same, suddenly my system drive loses all its remaining storage space. At first I was assuming that Lightroom copied over all photos so its own folders, which would be a frustration in its own right - but it seems like what's actually happening is that it's storing them temporarily until it can successfully sync them to the cloud.

This would be fine, except I only have 100GB of cloud storage on my CC plan and can't afford an extra TB - meaning that I simply keep syncing paused at all times. I don't mind this in itself, but it seems to result in this temporary file on my system drive filling up when trying to import my terabyte of pictures. I have tried the two local file-related settings but none seem to do much of consequence.

Is there any way I can set up Lightroom to work well with a large library of local files only, or is it not built at all for this purpose?