If you’ve been following biology news over the last few years, you might have heard of an interesting concept called a “gene drive”. The overall idea is to engineer a genetic allele that transmits itself to all offspring of a sexually reproducing organism, instead of being inherited by 50% as usual. This allele can also perform some other biological function (a relevant example is causing female sterility).
What does seem clear is that the mosquito population rebounded, with new genetics.
There is a long history of people getting these kind of ecological interventions wrong. 'What's the worst that could happen' is pretty bad.
> There are also plenty of bad arguments, such as that mosquitoes are ecologically essential. They aren’t.
The linked article https://www.nature.com/articles/466432a doesn't seem like very strong evidence that mosquitoes are not ecologically essential. The article quotes several scientists. Some of them say that mosquitoes are important, and some of them say they aren't. The scientists don't debate each other (presumably because each scientist was asked to make their case in isolation, without having the opportunity to hear what their opponents said), so you just end up with a bunch of assertions in both directions.
It's unclear why one would, from this evidence, conclude therefore mosquitoes are not essential. What I conclude from the evidence is "There's lots of disagreement among scientists, and we don't really know."
The reason is unintended consequences. Where does this type of intervention stop? If we start genetically re-engineering entire ecosystems and the planet to better accommodate our existence here it is a guarantee that we will ruin the place for all species. We, unfortunately, have the technological tools to do things way before we have the wisdom to properly use them.