As the submission explains, the lost+found folder has pre-allocated space for the directory entries. From the mklost+found man page [0]:
mklost+found pre-allocates disk blocks to the lost+found directory
so that when e2fsck(8) is being run to recover a file system, it
does not need to allocate blocks in the file system to store a
large number of unlinked files. This ensures that e2fsck will not
have to allocate data blocks in the file system during recovery.
Pre-allocating space without making the directory visible would require more arcane file system magic.
[0] https://man7.org/linux/man-pages/man8/mklost+found.8.html