Earlier quoted context omitted.
So one could file a bogus takedown for a competitor's website, etc. Ugh.
It's very unlikely that Google would follow through on an obviously wrong takedown unless if the competitor was actually infringing copyright. EDIT: Well, yes, they did do that here. My bad. My original point was that Competitor A submitting a wanton DMCA takedown against Competitor B wouldn't fly past Google's radar.
They will take down everything specified in every DMCA notice even if it is obviously bogus, because not doing so opens them up to a lawsuit. (a lawsuit alleging malafide intentions or a lawsuit for harm if they should make a mistake in deciding which part of the DMCA notice to honor and which to ignore.)
It is up to the harmed party (the owner of whatever was taken down) to challenge the DMCA takedown in a court. Once you win in court, Google will restore whatever was removed.