First it's "90%" of the mass of the universe, then it's "70%", then we're back to "98%", then there's dark energy, then the fractions change again, and again, and again.
This is not a correct characterization of the history of Dark Matter.
First of all, if you really studied Physics in university, then you ought to know something about uncertainties. If not, then, shame on the people who gave you your degree.
The history of dark matter includes observations on different scales that include different amounts of "missing mass". On some of those scales, we have accounted for some of the "missing mass" with different things-- e.g. some (smallish) fraction of the missing mass in galaxy clusters turned out to be in very hot intracluster plasma (which can be seen in X-rays) (and, even though it's a smallish fractoin, it's more mass than all the stars in the galaxies!). Something like 2/3 of the "missing mass" from cosmology-- which, incidentally, was always considered one of the weakest constraints on dark matter, since the uncertainties on the most basic parameters like the Hubble Constant were HUGE until the end of the 20th century -- turned out to be Dark Energy (which in fact might not be a thing, but a pointer to a flaw in our physics).
The numbers changed, yes. But uncertainties were huge to start with, so there's no surprise that the numbers changed. Trying to claim that the changing of the numbers indicates that the theory isn't making sense is a standard rhetorical technique that somebody who claims to know something about science should be ashamed to use.
Until some physicist demonstrates that dark matter is still required to explain measurements when the theory used is the full general relativistic model with speed of light delay included, I'm just going to automatically assume that dark matter is bullshit.
Go look up the Bullet Cluster.
The gravitational lensing values used in the calculations of where the mass is in that cluster come out of General Relativity.