There is no way in hell that steam would have this happen, the amount of money they have behind them combined with the name alone, no registrar would dare disable their domain without being damn sure what was happening was actually happening.

Stream would seek the registar for restitution/compensation, and if you take the yearly Revenue and divide that by the hours in a year they are approaching the $1,000 an hour mark. Of course this number would be different if they actually took it to court. But due to this alone I highly doubt their domain Handler(Mark Monitor) would touch that claim with a 10-ft pole without doing some pretty intensive research