Maybe it’s routes into Chicago from certain places? If it was Chicago as a whole, there would be an absolute flood of posts here that wouldn’t stop until the problem was fixed. Most of my time has been spent on Chicago servers since the expansion launched. This week I played a bunch, finished the campaign, hit 2k rating, and continued farming crests and gear. My ping has been a steady 56ms home/world from the South to Chicago.
Are you maybe joining groups that are on Oceanic servers?
When connecting to the VPN you mentioned, are you choosing Chicago as the location?
What is your home internet setup? What type of internet is it? It’s sounding kind of like 5G/Starlink with those latency values.