Tacoma bridge & other self-oscillators

I try to give a clear and succinct explanation, intended for students and teachers of physics at the undergraduate level, of why the famous collapse of the Tacoma Narrows bridge in 1940 can't be described as a resonance, but was rather a self-oscillation. I then explain the concept of self-oscillation and give some examples. I finish with a brief discussion of how the wind raises waves on the surface of the sea and of how that process can be understood as a self-oscillation (somewhat akin, in fact, to how the wind excited the torsional oscillation of the bridge at Tacoma). This is based on a presentation that I have some weeks before to the students of the course "Physics II" (for physics majors) at the University of Costa Rica.
Some of the references mentioned in the video are:
D. Green & W. G. Unruh, "The failure of the Tacoma Bridge: A physical model", Am. J. Phys. 74, 706 (2006), arxiv.org/abs/...
A. Jenkins, "Self-oscillation", Phys. Rep. 525, 167 (2013), arxiv.org/abs/...
Slow Mo Guys, "CD Shattering at 170,000FPS!" (2015), • CD Shattering at 170,0...
Pro-Level Civil Engineering, "Why Tacoma Bridge Collapsed?" (2023), • Why Tacoma Bridge Coll...
E. L. Mollo-Christensen, "Flow Instabilities", National Committee for Fluid Mechanics Films (1972), • (Audio corrected) 15. ...