Slightly different. The alternator on a car has a very variable frequency due to change in engine speed and it’s fed into the car’s regulator/rectifier, so the typical power supplied is stable. However, many cars will use the high beams at half-power to function as daytime running lights (DRLs). This is usually done by pulse width modulation (PWM) meaning it’s chopping up the power supplied at a nearly imperceptible speed. An incandescent bulb will have so much fade time that the choppy power will go unnoticed. From there, theses two possibilities that cause the bulb to flicker. Very cheap bulbs will show their choppy power supply directly by flickering, making them noticeable as the move across your vision. Some mid-range bulbs will have cheap smoothing circuits (since vehicle power is “dirty”) so there will be charge time and discharge time as the capacitors charge up and down, allowing and disallowing the emitter to light, creating a slower flash pattern. Higher end bulbs (ignoring the part where their beam pattern is still usually trash) should be able to accommodate the chopped power and run dimmer.

You may also notice a similar flicker on LED tail lights where the brake light is a brighter tail light instead of a dedicated element. Such cars will use PWM for dimming and may flicker as they move across your view as well. Some of my car’s dash uses LEDs for backlighting and dimming the dash is done via PWM. If I glance across the steering wheel from side to side, it looks like “cruise” gets stamped across the view