That traffic light "jumper" (I assume = cycling through red?), if it was done without being in others way, it wasn't a problem for anybody including the car driver "young lady".
I saw it too alot of times and I don't care at all, on that condition.
I do it myself, if it's clear (good sight) that there is no traffic, why waiting, it's for nothing?
Also the opposite, sometimes it happens that a turning driver has to let me first, but if I see that the driver while waiting blocks the way of alot other drivers that risk a second wait, I stay or slow down/stop and give sign can go first.
I'd never use a horn or yell or whatever for that reason.
Though happens. In city, foreigners neighborhoods, as soon after 1 uses horn, the whole row is doing it, drivers step out the car to go yelling at and knocking on windows, it's lol sometimes.
And when a wedding there, it's apparently a culture element to drive around the city in a long row while horning all the time, with eventually present police doing nothing about it.
In this case the driver shouldn't have reacted, but the cyclist also shouldn't have blocked her path later, a middlefinger response could be declared same "level", but blocking her that was beyond. But as just said, who knows, seeing it all from several cars behind, maybe the driver did more than use the horn and then things escalate further. But, there would have been no start if the driver had just ignored the cyclists act, and without start nothing to escalate.