As someone who's graduating in biotechnology, we want and we do, but there are a few things that make this not reach the market.

Round-up ready plants are incredibly easy to make, you insert only one gene (effectively, there are some little extra things but details) and now your plant can resist glyphosate, which means you can make many different species resistant to it much more easily, or make all of the different lines of whatever crop you sell also be restaurant to it.

For making drought resistant plants, there isn't exactly one gene that makes the plant resistant. Just one example would be root length. If a plant has longer roots it can access moist soil for longer periods of time and thus making it more resilient against droughts, but to make the roots grow longer you have several genes that interact and changing one might not result in deeper roots in a drought environment since that gene is activated by a phytohormone that is upregulated during long days (summer time) but this location only encounters droughts during early spring when the days are still short, and for you to regulate that gene to change when the phytohormone is upregulated you'd need to change a BUNCH of other things on the plant that would result in a complete mess of how the plant develops as now it acts like summer during spring but only for the roots and the roots send signals that the leafs must ignore until the correct time of the year and that changes when the seeds are going to be released because the plant is now blooming at a completely different time and oh fuck we've developed the equivalent of ancient Egyptian inbreed pharaohs but for plants, which is horrible but incredibly impressive given that most plants can self fertilize... This is one route of trying to just make longer roots, if we go through giving the root growth gene sensibility to another phytohormone that is upregulated on short days, the roots now will release other phytohormones in higher levels than the plant is used to (more length = more roots = more cells making said phytohormones) and since plants develop through gradients of hormones and the proportion of one vs another, the amount of work to make it so that the plant actually develops correctly will also be huge! And this is just for one single characteristic that we think would help in many cases but wouldn't actually make plants fully resistant to droughts, just able to get a few extra days of water, unlike how roundup ready is still just add this gene that allows the plant to break down glyphosate fast enough that it doesn't die.

Now the other side of the issue is funding. Yeah, droughts are a really bad problem for farms, but the BUG farms are either in places that they don't suffer from droughts that much, in places that they can buy a lot of water cheaply (government subsidies) or can produce a lot of crops even when there's a drought vs what they'd loose against weeds competing with their crops for water, nutrients and diseases spread by those weeds

In the end, we have the same reasons that tuberculosis and malaria are not funded and researched flash much as they should, it just doesn't make sense (commercially) to do so for big corporations like monsanto/bayer and the subject is complex enough that several universities having small teams researching it will tackle it from so many different angles and have such a difficult time with it that progress is really slow. The researchers want to work on cures for malaria, tuberculosis and to make plants resistant to droughts, soil acidification, nutrient content of the final produce and much much more, but we're fighting against capitalism and spaghetti code with no annotations written by thousands of not millions of different coders that didn't talk with each other through the millions of years of development of said code