You need to test APL1 before claiming a panel doesn't reach the advertised brightness, IIRC one of the writers of this site covered this topic before, some just do advertise APL1 numbers and technically they're not lying.
I recently just discovered that the 5000nits max brightness of the X11G is for about 1% APL, and not even entirely that, some other conditions need to be met for the TV to assess that >4000nits is possible(in terms of power and heat, I assume) and reasonable(in terms of the actual image rendered, because no current HDR footage is actually mastered for this brightness, so the system has to "guess" what should actually be so bright, it works like DSEE in lossy audio the way I see it). It's not to say that X11G's backlight is otherwise not an upgrade compared to X11 either, it's still about 30-50% brighter even at relatively high APLs so one could reach 1500-2000nits far more often with X11G compared to X11.
With its flagship smartphone, Xiaomi aims to climb the camera throne again this year in the smartphone segment. The 13 Ultra even uses four lenses with a 50 MP resolution and focal length of up to 120 mm. Find out here, whether the Leica cameras are convincing in our test and where the problems are again.