This just an FYI:
There have been 2 TWRP (unofficial?) releases recently for X00T/X00TD. Found one (v3.4.0-0, released 08-June-2020) on Telegram forum and the other on AndroidFileHost (v3.3.1-0, released 17-May-2020). In both, the native File Manager shows the contents of /system. But, - even after rebooting recovery and mounting /system - Aroma File Manager (run by flashing .zip file) does not. Also, USB OTG does not get mounted in v3.4.0-0. (BTW, both issues are not present in OrangeFox R10.1_6.) If anyone finds workarounds for both the above issues, please post here.