With the advent of techniques that make gene splicing relatively quick, simple, and cheap (as compared with the more arduous methods of the past), it's probable that the genie is out of the bottle and no effort of collective will ever be sufficient to get it back in. But that doesn't mean we have to accept genetically modified organisms (GMOs) in our food as inevitable.
I'm going to skip the whole GMO argument, at least for now, and cut straight to the chase.
Genetic modification in the laboratory is attractive because it can produce dramatic results for far less effort than the more tedious approach of breeding plants and animals in the field and on the farm. At least with regard to plants, robots can (in principle) change that, by automating the most tedious aspects of plant breeding, such as exerting some control over which plant receives pollen from which and labelling the seeds of each plant and keeping them separate from all the rest, as well as creating a record of the growth and vigor of each plant.
Taking over such tasks and thereby reducing the amount of work involved would make folding plant breeding into crop production possible, either as an experimental plot in every field or as a layer in the handling of crops in general. This, combined with techniques for sifting through large amounts of data, would vastly increase the number of plants involved in breeding programs, making the discovery of useful genetic recombinations or mutations far more likely.
By making conventional, phenotype-driven plant breeding both easier and more effective, robots could help shift the balance as compared with gene splicing in the laboratory, making it relatively less attractive.