I think the thing is, that each mass shooter murders for different reasons.

Some murder for misogyny. (Elliot Rodger)

Some murder for racism. (Dylann Roof)

Some murder out of some delusions or conspiracy theories. (Nikolas Cruz)

Some murder because they have a personal grudge against the specific individuals that they killed, due to being bullied/rejected/fired/etc

Some murder because they feel that the individuals they killed were representatives of a larger institution that harmed them in some way - this seems to be the case in this example

Some murder for religious reasons

Some murder because they have internalised homophobia (Pulse nightclub shooter)

Some murder because they are not gay but are homophobic in general

Some murder for unknown reasons

Yes it seems that people on testosterone (including this shooter) are more likely to express their anger via violence and that's a factor. But their gender was only one factor in their deciding to shoot people.

Also, there apparently weren't 130 mass shootings this year. According to the NY Times there have been 172 mass shootings (with 4 or more victims) since 1966.

It's true the vast majority of them were male.

But I think we should be fair - if we talk about "male violence" when mass shootings occur, and then when someone who isn't a cis male, commits a mass shooting, we shouldn't keep blaming everything on "male violence" but maybe look at the other factors involved more in all cases.