Describe the issue
It is documented in numerous sources that qcow2 images can be fragile and not as fast as raw images, please allow importing raw images and don't forcibly convert to qcow2.
Steps:
Edit->New drive->Import and select data.raw, notice data.qcow2
Expected:
data.raw

Note that it is possible to navigate to Library and create raw image, then everything works as expected, for example:
qemu-img create -f raw data.raw 250G
But will it be still supported in the future in that case ?

Configuration

• UTM Version: Version 3.0.4 (46)
• OS Version: 12.2.1 (21D62)
• Apple Silicon?