There were gas-spring arms for 80lbs+ CRTs, so i have to imagine they DO exist, probably just none for the current consumer monitor market since we haven't had consumer displays anywhere near that weight in quite a while. Also if you found one of those older CRT-style arm mounts, you'd probably need to modify it for the current VESA mount anyway.To be honest i do not think there is an ARM strong enough to support a 49 that high.
You can always get a tv arm that fully articulates to mount them. They are strong enough to hold a 65" + OLED.
That's how I mounted my 43" Aorus display to the wall and used regular gas strut monitor arms for the smaller ones.
SaltyNuts, did you see the 49" monitors in person?
The reason I ask is I just replaced my BenQ 3501R with a Samsung C49RG90SS monitor because I have a MSFS2020 setup.
The BenQ vertical screen heighth is about the same as the Samsung 49" BUT the immersion factor makes the Samsung "feel" bigger even vertically even though it is about the same as the BenQ. The BenQ is 35" 3440x1440 while the Samsung is 5120?x1440.
Just my opinion having owned and used both.