In the late-‘80s, a girlfriend introduced me to ‘T’, meaning ‘trash’. ‘What’s the T?’ (‘What’s up?’) she’d ask; or, Oh, she was dishing the T on [so-and-so].’ Recently I’ve seen posts where people use ‘tea’ for the same purpose.
I’ve never heard this expression. But I’ve heard of “spilling tea” with “tea” which referred to “gossip” and the “tea” meaning like gossip stereotypically old ladies would share over tea. That particular expression goes back to the 18th century, according to the online etymological sources I could find. Never heard of “T” for “trash.”
ETA: Actually, this cite has a different etymology, dating back to black drag culture:
I’ve noticed on Twitter that people like to talk about “spilling the tea”. Sometimes it means sharing gossip, i.e. “spilling the beans”, and sometimes it means launching into a lengthy, opinionated monologue.
“Tea” was a slang term for cannabis in the 1930s. If we have guests, I’ll occasionally ask, “anyone in the mood for some tea?” and as luck would have it, I’ll sometimes have to break out the teapot, cups, and cozy.
I’m pretty sure I’ve heard the idiom “weak tea” (to refer to an unimpressive statement) used decades before I ever heard “spill the tea”, etc. meaning gossip.