Chrome OS is based on the Linux kernel and designed by Google to work with web applications and installed applications. Chromebook is one of the best selling laptops on Amazon. However, devs decided to drop support for ext2/3/4 on external drivers and SD card. It seems that ChromiumOS developers can't implement a script or feature to relabel EXT volumes in the left nav that is insertable and has RW privileges using Files.app. Given that this is the main filesystem in Linux, and is thereby automatically well supported by anything that leverages Linux, this choice makes absolutely no sense.