Nanny's Big Brother has decided that the phrase "brain storming" is offensive to epileptics; therefore it should no longer be used.
Today a relatively "harmless" phrase is banned, tomorrow it will be something else.
As Orwell predicted, in his book "1984", an effective means by which a dictatorship can control the population is by controlling their thoughts. The best way to control the population's thoughts by controlling the language.
The elimination of words and phrases from the language means that people can no longer use them, or think them.
This is but the "thin end of the wedge".