The movie follows a group of people who try to survive from mysterious demons that cause mass suicides. If you see them directly, then you will die.
As a result of this film, many people create a challenge (Bird box challenge), where they attempt to go about their daily tasks while blindfolded, forcing Netflix to post a Tweet to address this dangerous challenge.
The concept of the "Bird Box" is very interesting and needs further investigation about what actually happen if this phenomenon really happened in real life.
#1 No communication System / Network
In the movie version, the presence of these demons makes communication networks disrupted, and many people die. In real life, the electricity network would fail within days, and the chances of survival are very small.
#2 Riots and Chaos
Looting and violence would increase rapidly when resources become scarce. The government would declare martial law, and most areas would become anarchy.
#3 Long-term Survival
There'd likely more survivors than you'd think. In the US alone, there are more than 21 million people reported to have visual impairments and around 1 million who are legally blind. And many people might be blind themselves using chemicals or surgical techniques for long-term survival.
#4 Further Threats
All that time we spend indoors would put us at risk for vitamin D deficiency and even depression. Besides that, poor nutrition and sleep would make most of us more likely look like Viggo Mortensen in "The Road" than Trevante Rhodes in "Bird Box".
#5 New civilization
Even though the global population would be decimated, there is still hope for humanity. Survivors would find each other, and form new communities with new means of communication. Then they would create a new civilization without sight and learn to live with their demons.