Odd that they didn't have at minimum 1) a physical Emergency Power Off (EPO) button inside the datacenter, such that one button could de-energize everything -- usually required as part of building a datacenter due to code variance for the "low voltage" (<4000V in this context...) wiring. 2) EPO interlink to the smoke alarms, such that it would de-energize equipment automatically (maybe with delay) if smoke detected.
The 2020 US NEC seems to have provisions for an EPO, but I'm not sure when it was added if it was present during the time of OP's incident:
* https://www.f-t.com/post/emergency-power-off-in-data-centers
EPO disconnects for generators was around earlier than the above:
* https://www.mgiepss.com/blog/emergency-power-off-epo
You'd generally not want to have the sprinklers go off while things were energized, but there could be a mechanism to monitor flow, and only cut power if sprinklers were actually sending out water. But even if this was present, your first priority would be for the sprinklers to not go off as there would be a lot of clean-up / drying needed after the fact.
Unless you have a mist system (NFPA 750), sprinklers put out a lot of water.