Some hate SegWit because even after its implementation, we are still having the scaling issues ongoing as well as the fees are getting higher and higher each day.

2. SegWit will deepen Core’s impact on the community - As an implementation reference for Bitcoin, Bitcoin Core was of significant influence in the community. However, their influence has long been overrated by their actions. By abusing their previous influence, they’ve obstructed Bitcoin block size increase from happening, against the will of the community.