Answer:
The 100KΩ maximum recommendation primarily addresses the FB pin offset current, which typically measures around 0.02µA but can fluctuate. If the Output Voltage (Vo) accuracy requirement has some leeway, using higher values is acceptable.
For instance, a 200KΩ resistor will double the accuracy tolerance compared to a 100KΩ resistor. However, higher impedance nodes are more susceptible to noise coupling. Therefore, it's important to keep feedback resistors close to the IC and away from noise sources.