Qualcomm Snapdragon 660 Advantages
Lower TDP (5W vs 8W)
Qualcomm Snapdragon 888 Plus Advantages
Better graphics card performance FLOPS (1.8534 TFLOPS vs 0.2176 TFLOPS )
Larger memory bandwidth (51.2GB/s vs 13.9GB/s)
Higher Frequency (2995MHz vs 2200MHz)
More modern manufacturing process (5nm vs 14nm)
Released 4 years and 1 months late