Because it's like Florida used to be...it's a demographic seesaw...it's been almost precisely 6 points right of the nation since the century began.
While the cities are moving D, the rural areas and exurbs are going hard R and aren't maxed out like in Georgia.
Also the 'burbs are only glacially moving D and started off last decade very strongly R.
Maybe it's a powder keg and it all collapses on the GOP like VA/CO did in '08...but I doubt it.
Not entirely true. It took a hard shift to the left in 2008 and didn't really go back to being the red state it was during the Bush years (yes, it still does have an undeniable GOP lean, but it's not nearly as strong as it was in the Bush years). In fact Bill Clinton in '96 underpeformed his wife in 2016. These are NC's presidential results from 1992 to 2020, with the GOP (in 2008 Democratic) margin given:
1992 - R+0.8
1996 - R+4.7
2000 - R+12.8
2004 - R+12.4
2008 - D+0.3
2012 - R+2.0
2016 - R+3.7
2020 - R+1.3
The GOP went from a double-digit win to barely winning the state. It's kind of what happened in Virginia except North Carolina slowly drifted back into lean Republican mode and stayed there (the last time it gave either party a margin greater than 5 points was actually 2004), while Virginia (and for that matter Colorado as well) just continued shifting leftward, particularly in the age of Trump, supported by (sub)urban growth and liberalization and demographic changes.