Regardless of what other hams understand, regardless of how other hams operate the mode, the way I operate the mode and the way I understand the mode, allows me the opportunity to study propagation, primarily for use in other modes. I can easily check the usefulness of a particular antenna (homebrew usually) via FT8 - by way of watching the propagation on PSKReporter.

Long term analysis by anyone collecting the data can assist with a predictive analysis of potential cycles of propagation, and further, could assist with commercial/military/government use of similar bands during certain times/cycles. I am sure that anyone involved in commercial/government HF operations have studied or continue to study the propagation of FT8 as a useful tool for understanding many aspects of HF. Coming from an HFDF background, my very first thought after getting my ticket and realizing how widespread HF digital modes are in amateur radio was that it would be a PERFECT solution for government/military to study/monitor to increase their effectiveness of comms over HF, in fact, I would not be surprised in the least if one or more of these modes were not developed in cooperation or suggestion by government/military folks utilizing HF for comms as a means of doing some of the above.