My 2 cents is that they just have different methodologies driving them. Sia is shipping a working network early and updates are arriving often. Filecoin seems

My 2 cents is that they just have different methodologies driving them. Sia is shipping a working network early and updates are arriving often. Filecoin seems to be taking an approach more like Holochain stuff. Meaning they are shipping early and often but only internally and you'll get to see it when its ready™.