OS: Ubuntu 18.04.6 LTS
HDD: ST1000LM024 HN-M101MBB (1,0 TB)
SMART: Disk is OK (3 x Pre-Fail, 20 x Old-Age)

I needed to copy 20 MP4 files from old laptop to brand new ADATA 64 GB flash drive. The smallest file was 420 MB and the largest file was 5,8 GB (43 GB in total).

There are 3 ways of formatting a flash drive (ext4, NTFS, FAT). I tried them all. FAT resulted in "File to large error", NTFS resulted in "Error splicing file: Input/output error" and ext4 was a success.

1. Why only ext4 was a success?

2. Can I now copy those files from ext4 flash drive to Windows 10 or macOS?