The reason they're so bright and annoying is that you, dear motoring public, love complaining we're "not visible enough" in the comments of newspaper articles about people killed while riding a bicycle. Or in letters to the editor. Or to your legislators. Or at hearings about road infrastructure. Or hearings about road safety legislation. Or after you've plowed into one of us.
If you all would like to work on the whole "not killing large numbers of vulnerable road users", we can certainly look into the whole "make our bike lights not blink."
My state requires, at night:
* a rear light visible more than 500 feet * a rear reflector * pedal reflectors or ankle reflectors (both ankles) * front reflector (+500 ft) * front light (+500 ft) * wheel reflectors
Our state used to only require a rear light, but a state legislator refused to let a road safety bill pass unless he got put his paws all over it and increase equipment requirements for cyclists to "balance" out requiring drivers must give cyclists a minimum of three feet passing distance.
And yes, sometimes it is necessary to use a blinking mode to assure that we won't run out of battery (and thus have NO light) before we get home. On a long ride, for example, or in wintertime when lithium ion battery capacity plummets.
Except for all the dead cyclists of course.