Outdoor farming is still incredibly resource intensive. As we move into an age where unsalted water becomes more precious and rare we should focus on hydroponic growing tech to preserve water. It is indoors so it wouldn’t require pesticides.
Of course the greenhouse has advantages too--you can deliberately introduce beneficial (predatory) insects and they can't fly away, and if you do end up using pesticides then there's no risk to wild pollinators. For example, the EU banned certain neonics outdoors but still permits indoor use. It's more just different than strictly easier or harder.
Of course they do lots of hydroponics too, for the usual hydroponic crops (tomatoes, cucumbers, etc.). The science in hydroponics and science in sophisticated soil culture aren't really that different--you'll see mostly the same chemical fertilizers, the same EC and pH measurements in the field, the same lab analyses by ICP, etc.
Some water still drains to the aquifer and is "wasted". It needs to be though, or else unwanted ions (from impure source water or fertilizer, including but not limited to Na+ and Cl-) would accumulate and kill the plant. Israel has a significant problem with salinization of their soils and groundwater, and lots of interesting work modeling that.