LineageOS instead extracts these from the official ROM.
RE and/or shimming only need to happen when those BLOBs become incompatible with newer versions of Android.
The actual task of a maintainer is to configure the rather generic AOSP/LOS to work with the device’s specifics and integrate device-specific components.
For a few simpler examples, it must be configured which of a device’s SIM slots (if any) are eSIMs, which brightness values the device’s light sensor is expected to return, where the device has a fingerprint sensor (if it has one), the dimensions of the notch cutout and many other such things.