The biggest reason it may be different this time is previously we were all like, “let’s exterminate dogs,” and it turns out dogs are important. This time is more like “let’s exterminate pitbulls.” There will still be plenty of mosquitos around if the plan is ever put into motion, we are only targeting a very small slice of them. That doesn’t mean there won’t be issues, it could well be just as big a mistake as all the previous times. But at least it is more likely to work out.
Well, like I said, there is still a chance of collateral damage, which is why there has been so much study to try and make sure that isn’t going to happen. We’ve been sitting on the ability to do this for a long time. As for chances of killing other species, I don’t think that is a risk from the method. They basically just breed mosquitoes of the targeted breed, and modify their genes so they can only have male offspring which can also only produce male offspring, etc.