CanoScan LIDE 700F no longer works with iMac Sequoia 15.6.1

The LIDE 700F is a very old scanner and the last known driver for it was on macOS Mojave, dated 9/2/2018.

You could try using Vuescan. It has its own built-in driver for the 700F.

To answer your macOS question ... after Big Sur came Monterey then Ventura, Sonoma, Sequoia and now Tahoe.

It is true that the LiDE 700F is supported by VueScan Professional without any Canon drivers or software. Canon abandoned driver support for this older scanner years ago. Only VueScan Professional will allow you to continue using the LiDE 700F on Sequoia and later, without the much greater expense of a new flatbed image scanner.

As a side note, the LiDE 300 and 400 flatbed (non-image) scanners are still supported by Apple's built-in AirPrint, even though these USB-attached devices are not mentioned in the AirPrint supported devices material. Tested my 89 USD LiDE 400 on macOS Tahoe 26.0 with Image Capture and it works. Same with macOS Sequoia v15.6.1, and v15.7. These two newer models are also supported by VueScan Professional without Canon drivers or software.