Here come the slaps!
"Pennsylvania is trending republican" is a lazy bush league political analyst talking point with no basis in reality.
The margin of democratic votes over republican votes has grown every year, with the exception of 04...when the state STILL went blue when every other swing state went red that year.
It's trending democratic, not republican. Is it trending democratic more slowly than the rest of the country? Well yeah, no shit. This country's growth is fueled largely by immigration, most of that Hispanic.
PA is one of the whitest states in the country with a black population at the national average and a Hispanic population about half that. The explosion in the Latino population along with the associated democratic votes isn't happening here.
What IS happening is that the growth in the state is occurring in the Philadelphia and Pittsburgh metro areas, which are extremely well educated, millennial, and urban. The coal country and steel town populations in the middle of the state where conservatives live are dying out.
This is a slower process than a million Puerto ricans heading over in a boat, but it's no less irreversible.