how serious is it in practical terms if some yutz waves a store-bought pointing device skyward?
I welcome you to join us in our 'office in the sky' and find out for yourself the effects a sudden unexpected laser light being shone into our 'office' can create. You seem or appear to have a lack of the knowledge of experience in this very dangerous matter.
Unlike in a car we continuously scan our instruments, and when approaching to land look both inside and outside repeatedly to ensure a safe outcome of the flight.
Searchlights, beacons, all lights similar to those you described, none of these bother us when flying in the slightest. They are all around airfields and we see them daily. But lasers are a different issue.
Lasers can temporarily blind you or in worst case scenario both of you, while manoeuvring close to ground at very high speed in an until then controlled vehicle far in excess regarding speed and weight then any car travelling the roads ever will. If it doesn't blind you it will startle and distract you maybe enough from achieving a stable approach with all possible results.
One day such vehicle will have an accident and the results will be disastrous, but the aircraft upon investigation will be another perfectly serviceable machine, brought down by human error.