(a) If the good Doctor is concerned about the exploitation part of prostitution, then she should consider legalizing (or at least de-criminalizing) it so that those in the industry can go to police to report abuse without fear of being locked up themselves, can unionize, and can generally make more ruckus about better working conditions. The State of Nevada has legalized prostitution and while I don't have figures to hand (ha!), my guess is that labour conditions are more favourable there and incidents of abuse/ exploitation are lower than in other states.
(b) Ditto everyone above who has pointed out the "vibrators good, sexbots bad?" incongruence. Not necessarily my cup of darjeeling, but I don't see how having more options available for folks to scratch itches is a bad thing.
(c) Comments about "finally, being able to get a shag without all the human baggage -- arguments, bribing with dinner and flowers, threats of partners withholding bedroom action" would suggest that sexbots could certainly solve some of the symptoms of a relationship mismatch but won't cure it. This of course, is one of the many areas of compromise/ negotiation that each couple has to decide for itself.