She corrupted turning all CASTs on her community mad, and must be destroyed to stop her corruption from spreading and Phantasy Star Online 2 Meseta wiping everything out. Also, it's not exactly her fault, but there is a similar satellite-collision episode in PSU's plot - the colony the PSU equal of ARKS is inscribed on orbits Parum, and is sabotaged badly enough that its orbit starts decaying and the residential sector needs to be gleaned from the remainder of the boat, resulting in the remainder of the station crashing to Parum - it does not ruin it, but it wipes out a town, also leaves a huge crater and uninhabitable area around the wreck site.
The Mother in PSO2 is an artifical creation of this Photoners (along with the Photoners are similar in some thematic ways to what is seen of this PSII Earthmen, IE arrogant and egotistical ) that manages Earth, and during the course of EP4's story she's tainted by Dark Falz/Profound Darkness.
This Mother is redeemed, but killed by EP4's real antagonist afterwards. Before it could her stays try to destroy Earth and wind up being corrupted by DF/PD, but are finally destroyed.
And all of the various versions of pso2 buying meseta Mother during the show share a lemotif, that being"The Place of Departure", the subject that has been utilized during her boss struggle in her first appearance in PSII. Her other themes are:"MOTHER" at PSU,""IDOLA" the Imitated God" in PSZ (it is somewhat more subtle in this version), and"The Position of Death - Esca Falz Mother" at PSO2, in contrast.