Their natural predator in China is a parasitic wasp which, if introduced, would likely decimate native insect populations. The government is considering it as a last resort, but as you can imagine it's not a pretty alternative.

For protecting specific trees, you can get sticky wraps that surround the trunk of the tree: https://www.farmanddairy.com/top-stories/how-to-install-stic... . A friend of mine has employed one to great effect.

Parasitic wasps are often highly specialized, so it's not clear to me it would decimate native insect populations.

This is true. Actually discovered my first oak gall this season and reading up on the specific wasp that can make an oak make an apple and then the specific wasp that puts parasites into the parasite and so forth. Anyways, fascinating.

https://en.m.wikipedia.org/wiki/Oak_apple

Another step you can do is locating any egg husks on trees in your yard and scraping them off. At the very least it'll keep the nymphs from showing up on those next year.

Penn state ag department has some good resources on the fly

https://extension.psu.edu/how-to-remove-spotted-lanternfly-e...

If it's otherwise healthy, they won't kill it or even hurt it that badly. They loved the black walnut in our yard and I was worried about it, but by the next year they were mostly gone.