Here in suburban Philadelphia we had a huge number of them three years ago, but far fewer in the last two years, and almost none this summer. My husband is an expert lanternfly smoosher. :-)

I wonder why the difference, Philly is not that far away. Overall, I see more pests this year.

This is an article from last summer:

People in Philadelphia and the suburbs may now be seeing more spotted lanternflies, as late summer is when the insects mature into adults, grow wings and take flight.

However, reported sightings in the region have declined since the invasive, crop- and fauna-destroying species first made it to the city five years ago.

The number of reports in the city shrank by 92% between July 2020 and 2022, from 7,877 to 575, said Shannon Powers, the Pennsylvania Department of Agriculture's press secretary. The drop was even more dramatic in the suburbs, where reported sightings shrank by 95% over the same period, from 19,652 to 839.

But scientists aren’t sure what's causing the decline.

https://www.phillyvoice.com/spotted-lanternfly-population-decline-pennsylvania-bug-invasive-species/

I am north of Philly, never been worse, north and east of Philly by 100 miles. Will these bugs keep the highly invasive Ailanthus in check here? These invasive insects and trees ebb and flow depending on who knows what. Years ago, we had a big issue with Mimosa and those trees seemed to go in a steep decline, no idea why.