What is that reduce the number of transactions? you can't stop people from transacting, segwit does it by reducing the size of the data included in each block. who opens channels in LN?
Probably he is talking about the reduced of unconfirmed transaction once SegWit is implemented. I believe that is the purpose of Segwit, to establish the fix for bitcoin scalability if I am not mistaken. It gives way to Lightning Network that will greatly help in the transaction.
And also it would just lower the transaction fees in any transactions. It really would fasten transactions because of the reduced amount now that the witness or blockchain has its own. but i think it is not enough for the growing problem in the blockchain recently. i would see hardfork also as a good solution for the blockchain. Other than that i observed segwit is really helpful in other coins as far i have observed.