Ive seen this issue in maybe 8/10 youtube reviews of the monitor but none of the reviews actually state them, so last week I tested a total of 5 PG348Qs with a batch made in June 2016 (3) and December 2017 and 4 out of 5 had the same issue, is this just simple quality control issue that is left unresolved until today?

This can be checked by going into windows personalization then choose solid colors and just cycle through the colors and its very visible on blues/greens/greys or anything not yellow/orange/red.

Aside from that it seems that the scanline issues are still not fixed even on a dec 2017 (2) build date.