Everything can be explained by invoking Dark Matter.
Something Is Not Quite Right In the Universe, Ultraprecise New Measurement Reveals
Space.com ^ | February 9, 2019 | Mara Johnson-Groh, Live Science Contributor
Posted on 2/9/2019, 12:49:05 PM by ETL
https://www.freerepublic.com/focus/f-chat/3726592/posts
Zwicky was the first to propose the existence of dark matter based on the rotational velocity of galaxies. Galaxies are rotating too quickly for gravity from observable stars to hold them together. Black holes don’t work, because if the matter were concentrated at the center the outside would rotate more slowly than the inside, just as Pluto orbits the sun more slowly than Mercury. Zwicky concluded that if Newtonian mechanics explained the structure of galaxies there must be some unseen matter more or less uniformly distributed throughout the galaxy holding them together that did not show up in telescopes. Hence the term, dark matter.
The nature of dark matter is not known, no compelling evidence for any particular form exists, although neutrinos and failed stars (super Jupiters) has been ruled out.
Regardless, dark matter does not explain the discrepancy between estimates of the Hubble constant resulting from different measurement techniques.