No, it’s not a joke. When driving, cars and the like are often indicating or have their hazard lights on, but it is frequently impossible to tell the meaning, as usually only one side can be seen.
The older car had a mechanical flasher relay, using a simple but robust metal strip which heats up and toggles the lights on and off (a little like when ghost researchers fake ‘ghostly communications’ with a half-off torch that flickers due to heating effects).
Modern cars, on the other hand, have a CPU that does the job.
So, could we not mandate that the hazard flash had a different timing to the indicators? Well, how would you know if it was just running slow or something (which a low voltage caused in those old mechanical relays, as well current means less heating).
The answer? Program a double flash, or some other differing flash sequence. This would tell you what was going on even if you could only see a single bulb, from any angle.
Seeing a nose of a car with a double flash (say, flash, short off, flash, normal off, repeat) would tell you it wasn’t an indicator in a short time, unlike the current situation. Safer for all.