They log old growth and plant a single species in what was previously a diverse ecosystem.
Not just that, but often an invasive species. That said, cities are just as bad on that front, allowing developers to put Bradford pear trees in every subdivision. They grow very quickly and flower early in their lives, so developers love them. They also reproduce very quickly and the flowers stink. They’re also pretty weak and tend to blow away in storms where they end up doing things like going through someone’s car. Then they escape and get everywhere. If you see white-flowering trees blooming in the spring on highway off-ramps and you notice more of them every year, that’s why.
On top of everything else, they don’t actually produce pears.