companies have plenty of political power
No they do not. Companies are not cognizant. The people inside a company are the ones with the power. If you want to hold someone accountable hold the person whose actions are actually causing harm to this country, not a political ideology.
Just like AC's.
Instead the robot can set off an alarm
Which is known as a deterrent. A quite good one at that.
As for better than a security guard, that remains to be seen. But between an overweight, mouth drooler with a can of pepper spray meandering a parking lot and a mobile recording device capable of blaring noise, flashing lights and bringing lots of unwanted attention, the latter seems better to me.
Just for starters, the latter has a perfect recall of the preceding events. Good luck getting the height or sex or anything useful from the security guards story.
Kiss your keyboard goodbye!