AVI No Longer Supported MAC 2018 but still listed as Supported.

[55878965]

AVI used to work, now it's dead dead for a MAC system and windows it seems too.

https://helpx.adobe.com/premiere-pro/using/supported-file-formats.html

2018 - No longer supported for MAC but it worked sometimes up until version 23ish.

 https://community.adobe.com/t5/premiere-pro-discussions/avi-files-no-longer-supported/m-p/9852864