ext4 and Btrfs are only well supported on Linux; they are not universal standards.
NTFS was only supported well on Windows until recently; but extensions like NTFS Encryption (BitLocker) are still Windows only. Mac still does not let you write to an NTFS volume.
APFS and HFS+ are obviously Apple file systems.
FreeBSD does not support ext4 or Btrfs well; but instead prefers UFS2 or ZFS despite also being an open-source Unix-inspired OS.
The world runs on proprietary or non-universal file systems with CDFS (ISO 9660), FAT, and exFAT being the sole exceptions.
NTFS was only supported well on Windows until recently; but extensions like NTFS Encryption (BitLocker) are still Windows only. Mac still does not let you write to an NTFS volume.
APFS and HFS+ are obviously Apple file systems.
FreeBSD does not support ext4 or Btrfs well; but instead prefers UFS2 or ZFS despite also being an open-source Unix-inspired OS.
The world runs on proprietary or non-universal file systems with CDFS (ISO 9660), FAT, and exFAT being the sole exceptions.