I am also have the question about OP questions. So i search some possible factors why segwit is not that popular to most of us. Will highlight the important matter.
1. SegWit doesnt solve the most urgent capacity issue - SegWit, which is a soft fork solution for malleability, cannot solve the capacity problem.
2. SegWit will deepen Cores 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, theyve obstructed Bitcoin block size increase from happening, against the will of the community.
3. SegWit makes it harder for future block scaling - On technical terms, SegWit uses a transaction format that can be spent by those who dont upgrade their nodes, with segregation of transaction data and signature data. This means SegWit is irrevocable once its activated, or all unspent transactions in SegWit formats will face the risk of being stolen.