For example, this relativistic MOND-inspired theory is supposedly consistent with observations from CMB and gravitational lensing: https://physics.aps.org/articles/v14/143
There is also Jonathan Oppenheim's body of work on stochastic spacetime which supposedly accounts for these observations without needing dark matter (and it also doesn't need dark energy): https://www.theguardian.com/science/2024/mar/09/controversia...
It feels like the community is stuck in dogma, and is in need of a paradigm shift. I'd like to see more effort and funding towards testing alternative theories. I'd also argue strongly for more investment in space telescopes that could further our understanding, especially given how much JWST has already provided evidence against the standard model of cosmology.
About $6 to $11B have been spent trying to detect dark matter over the past 30 years or so, and nothing has turned up. Investing in testing alternatives and efforts to gather data that would help refine hypotheses seems like money well-spent to me.