instantaneous vehicle speed

Not too bad: https://www.azosensors.com/Article.aspx?ArticleID=11

Per matters
PW does not.

Vehicles pre 2010 use a seperate vss on the gearbox, 4 or 6 ppr of the wheel, later vehicles than that seem to use one of the abs sensors for vehicle speed.
The low duty wave above looks much like a abs hall effect sensor o/p.