A lot of Phoenix Elves' value is setting up board situations where the opponent can’t find value, and Blinding Flare is the maximum representation of that strategy. It’s not cheap, and it is very hard to set up (though Call Protection helps).  But when you do get a quality Blinding Flare it can really make your opponent almost skip their attack phase altogether.
In addition to that it can allow Maldaria to push safely that turn, knowing it’s going to be very hard to be punished, gaining control of some specific area and hopefully setting up a forward gate, pressuring the opponent. 
Setting up key Blinding Flares is part of Maldaria's strategy, and this is especially true when Maldaria needs to go onto the offensive.