Am I wrong, or were the Geth built by the Quarians?
That's a rhetorical question.
They are not living creatures, no matter how much you may want to take sides with them. Bender would want to kill me right now, but the Geth are robots, nothing more. They may have A.I. and have a collective 'consciousness' like the Borg, but they are NOT alive. Which would you prefer, people performing tests on animals or performing tests on robots? The answer is obvious, because humanity is trying to stray away from animal testing every day, and we build more and more robots to perform the dangerous tasks that can risk lives.
The Quarians built the Geth for whatever purposes they want, and they have the right to test/damage/destroy them. Yes, the right. It's the same as forging a sword in order to spar with it. The Geth put on a good show of acting alive, of acting as if sentient, but they are machines. No matter how you break it down they are the same as toasters. They only exist due to the programming some genius Quarians implanted within them in the first place.
The Quarians did make many mistakes, the primary being that they built something stronger than themselves. However, the Geth should be abolished entirely like a model # from a factory that is defective. They, the Quarians, do not deserve for one second to be punished or to have war waged against them. It's a shame there isn't some grand switch that can be flipped that easily shuts down all the Geth. Hopefully there is actually, and in ME3 you and Tali will trudge to the Quarian homeworld to flip it (metaphorically, because an actually switch would be terrible writing ;p).
P.S. I love Legion and my Para-Shep supported him while using the Paragon option to keep Tali satiated. This I chose for story purposes. My Rene-Shep is entirely against the Geth, even the non-Heretic forms.