tlance
Kyrie Hater
Siakam avg more than him by about 3 PPG so yeah Lowry isn't exactly their 2nd option.
Siakam avg 17 on 54% shooting and 37% from 3.
They also have other veteran guys like Gasol, Ibaka, Green, Van vleet etc. who provide strong complimentary scoring options.
IMO, Lowry's value is irreplaceable because of his facilitating prowess and his defense. Scoring is gravy on top for him and when he is scoring they are as good as anybody outside of GS.