Gmail allows users to categorize messages into different tabs based on their content.
For example, I have messages from mailing lists like Google Groups go into one category, while all others go into the other.
aerc groups all of these messages, which means that the default INBOX folder is crowded. Ideally aerc would allow me to view Primary and Forums as either separate tabs or as folders in the sidebar.
Unless you know of a way to do this via IMAP...
Looks like Gmail doesn't support it.
After some research, I settled on labeling incoming messages as a workaround.