That is true, both are using UBUNTU but elementaryOS and POP_OS have done many changes compared to the UBUNTU. I have tested many disctros and I am for two years using elementary without any changes. And I am hard user which means I usually work for 12-16 hours a day.Yes, but I'm a KDE fan and they're technically using the same Ubuntu core so I use Kubuntu
I believe it worth to give it a try.
POP_OS is well integrated to the hardware which System76 is offering however, my personal experience and also other people's reviews around the web and youtube have been really posiotive even on none-System76 harware.