I think you should decide for yourself whether that is an acceptable amount of back light bleed, you are the one who has to live with it not me or anyone else on here.
If you really want my opinion, that looks terrible that is not a "little" bleed that is a lot in my opinion. Your replacement will likely look terrible as well, the PG279Q's are plagued with backlight bleed. I own one, which I got quite cheap because of it's terrible backlight bleed, excellent monitor besides this one pretty substantial flaw.