Sync iTunes on Windows 10/11: Slow file transfer speeds with iPhone 15 Pro Max compared to old iPhone 7 Plus

I bought an iPhone 7 Plus when it was the newest model and used it until it finally died. I replaced it with an iPhone 15 Pro Max. I noticed that the file transfer speeds are a LOT slower now with the 15 Pro Max (USB C connection on PC) when synchronizing my music files with iTunes running on both Windows 10 and 11 machines. It takes at least twice a long as before. It doesn't matter what USB C cable I use. I got a USB C data cable from my local Apple store to make sure. What gives? Is there a configuration setting I need to change somewhere? *scratching my head*

Thanks in advance.