Why if a smartphone can shoot 4K 30fps video, then why is there no FHD 120fps mode in the settings?

Question

Android

After all, if a smartphone can shoot 4K 30fps, then 4K÷4 = FHD, since FHD resolution has 4 times fewer pixels than 4K, which means 30fps x 4= 120fps at FHD. + FHD also has a lower bitrate than 4K, which means it’s much easier for a smartphone to shoot ...

Answer 1

Almost all manufacturers underestimate the functionality of the camera when using third-party applications, this is probably done on purpose so that this equipment cannot be used for anything other than a 'smartphone' (the hardware is now installed there so cool that some professional hardware can stand nearby, yes of course there are other problems, but still ) although it’s more logical to just marketing, to distinguish between expensive and cheap pieces of iron through functionality, selling in fact the same piece of iron.
Those. a video shooting application from the manufacturer can shoot video in extreme modes (for example, my xiaomi redme note 8 pro has the ability to shoot fullhd - 120fps or hd720 - 240fps), but google api gives third-party applications a maximum of 60fps, to fix this you need to look for firmware modifications for your platform , for example on w3bsit3-dns.com, fixing this (and their installation itself already requires special skills, since an error can corrupt the device)
ps