Yes and No. Layer to layer training of deep belief nets were doing very well before alex.net came along, although alex.net was seminal for images. People often miss the big &#x27;advances&#x27; in RNN&#x27;s, although those go back to the 90&#x27;s and earlier. A lot of this (but not all) is also due to more data, better and faster hardware (including GPU&#x27;s). Although there have been some important algorithmic enhancements too.