Why did they decide to keep it low .. less iso less shutter speed ... Why?
More ISO more noise so swings and roundabouts and all that, it seems common practice for manufacturers to cripple hardware.
On my favourite Canon Travel camera the slowest shutter speed is 15 seconds but some plonker at Canon thought it would be a good idea that once you got passed a 1 second exposure to limit the camera to ISO80. Now this camera has a decent backlit CMOS sensor, produces relatively noise free images up to ISO1600 and yet they have made it useless for capturing night scenes with a timer and a tripod, the limitations they have imposed make it impossible to capture enough light.
Camera sensor size and quality determines how much noise can be processed when ISO is increased. Software/processing can reduce the effect as well. But, the sensor is only 1.12ums compared to 1.22 for iphone x, 1.4 galaxy s8 etc.
Higher ISOs are nearly always going to produce more noise and less detail in low light situations regardless of sensor or pixel size.
Even when using DSLRs i find myself resorting to Neat Image from time to time.
Of course it is true, even a full frame DSLR will suffer noise at high ISO, it is even noticeable on a professional level Canon 5D MKIII at ISO 800 https://www.the-digital-picture.com/Comparisons/Canon-EOS-5D-Mark-III-DSLR-Camera.aspx
Not quite true, the bigger the sensor the more light it can capture,
plus, the less mega pixel even though less detail will produce better
low light performance than higher mp count.
Believe me it is true.