Nope, "AI". The academic community working on one very active research area of traffic analysis, called website fingerprinting, made significant leaps with NNs over traditional ML in 2018: "Deep Fingerprinting: Undermining Website Fingerprinting Defenses with Deep Learning", by Sirinam et al., https://dl.acm.org/doi/pdf/10.1145/3243734.3243768 . Since then, the most powerful attacks here have used deep learning.

Broadly speaking, traffic analysis benefits a lot from work in computer vision: view a network trace as a one-dimensional picture. There are some fun visualizations here if you scroll down a bit: https://github.com/pylls/padding-machines-for-tor/tree/maste... . Every 1-pixel high line is a website visit, where each pixel corresponds to a packet (or cell in Tor) sent or received.