It never went anywhere. Some core companies still produce smaller boards. Real, toy machine, thank you, almost, to name a few. Really it's dependent on the truck companies. The smallest option for most brands are 7.6".
I got a size 9 shoe and anything bigger than 8.25 feels like a boat. I'm skating an 8.25" with 8" thunders right now. I switched to the bigger truck from a 7.6" thunder. I would always miss feebles and krooks on the smaller truck. but my flip tricks felt amazing. I switched to the bigger truck and I don't think i've missed a krook or feeble. But my flip tricks feel slower and shittier. I might try and skate an 8" for my next board.