So why in the fudge are they being so damn negative about this? Is this really that stupid of a plan...If it is please tell me why? Or are they just too caught up in the yard landscaping city mindset to even conceive of this?
These are very different questions.
The first one is something worth of a meditation. "Why people is negative about your efforts?" Some people might care about you, wasting your time and making yourself angry, but this is the less likely. Some other people might just want to show how knowledgeful they are, to compete in this game of domestic politics where everyone must show some value to be a worthy member of this society. Then, other people might just be scared of you, since you are proving to think very differently than them, and these people can't stand diversity (these are the same who will burn anyone not sharing their religion a few centuries ago). There could be other reasons, but these are the most probable, in my opinion.
About your other questions, you've been offered good advice, I think. Many of us love to give advice, and here goes mine:
Every land is unique. You have to observe it carefully to learn about what can be done and what not. If you want to plant pear sapplings, look at what pear sapplings need to thrive, look at what your land is offering to the sapplings, and then think what you can do to make a difference. Of course, pears are not desert fruit trees. But pears can endure mediterranean climate. Maybe you can develop a desert variety from a variety that is adapted to extremely dry mediterranean climate. Still, you will need to work on your microclimates to achieve that extreme mediterranean climate, closing the gap. Irrigation, shades, heat storages and wind breaks are tools for building microclimates. If you don't want to work like a mule in the future, try to create your microclimates in a way that are self-sustainable. For example, using water retention structures you will make better use of the little water you might receive, and it's much better if your plants get the water directly from your water retention structure rather than depending on you for watering.
You will be introducing a species from a very different ecosystem, so your desert ecosystem might reject it in the first attempts. If you want your pears to thrive, they need something more than a proper microclimate, they need a supporting ecosystem. Without a proper diversity of thorny, poisonous, smelly and other ugly plants, and also dangerous animals your lovely pears might not have a chance.