With all due respect to theorists, everyone in particle theory and cosmology is doing this sort of thing. I remember in grad school, cohort-mates down the hall

With all due respect to theorists, everyone in particle theory and cosmology is doing this sort of thing. I remember in grad school, cohort-mates down the hall whenever the LHC announced any sort of blip would rush to get a preprint from nothing in a week for the chance to be the one to have made a discovery that fits the discrepancy. One theorist even told me the lack of experiment was "good" because they had space to keep churning nice theory papers without having to worry about being shot down. Occam's razor suggests to look at explanations that are mundane first. Even beyond dark energy candidates, it looks like Axions are another explanation which is more well established in the theory world (for what that's worth...), so absent more data it's hard to say it's an observation yet without elimination of alternatives.