This seems like a stretch. Media certainly fits both of these, but it's hard to claim academia is in decay by most measures, and I have no idea how you could possibly claim American government or military are illegitimate OR in decay without resorting to completely subjective measures, such as how partisan the republic is or how few things get done (of the things you care about, no doubt).
(Note: one could construct a plausible claim that military is in decay based on what percentage of spending goes to operations instead of R&D and acquisition[0], but I'd argue this doesn't mean our military is in decay so much as entering a period of restructuring as a result of a series of unfortunate long-term planning misses)
[0] as seen on HN, https://scholars-stage.blogspot.com/2021/04/welcome-to-decad...