I have been following this project for quite some time. It appears that a lot of accumulation has been happening (or bag loading). There are many contributors to this project, which has a working product with important developments coming in 2019. It probably fair to say a elements of the core development team have been distracted with the creation of the ASIC mining company obelisk. Some might criticize the decision to get involved in developing hardware but recent attacks on some coins may yet prove the team has been prudent. The team openly acknowledge the conflict they have in creating hardware that runs on the network and have taken some steps to remove themselves from this conflict.
SIA hard forked Bitmain and Innosilican miners off the network by resetting the POW algorithm last year (https://blog.sia.tech/sia-proof-of-work-...).
Things appear to have settled down and the devs appear to be focused on the next release.
With regards to the chart, I know there isn't much there by way of FIBS and but it does look like a has formed - Onwards and upwards from here (maybe). Longer term the block reward is declining fast and will settle at around 30k per block in 2020. This will mean anyone that is mining it then, if they want to make a return will unlikely sell the token unless it covers the cost of their mining operations. (https://siastats.info/macroeconomics). Interestingly SIA hosts burn coins when using the storage product, so the more people use storage the more "burn" so if SIA usage grows the price will rise. This is more of a long term investment in my view.
for disclosure: I own several Obelisk ASICs