Not really. It is a hypothesized form of matter. There are competing hypotheses. Dark matter came to popularity in order to explain observations of galaxy rotation curves in the late 1930s. But these galaxies were observed in isolation, giving the illusion of gravitational isolation, which doesn't exist. Once accounting for the tidal effects of nearby galaxies, [1] dark matter becomes unnecessary to explain galaxy rotation curves, all that is needed is Newtonian physics. But in the period since dark matter was hypothesized, other observations that could not be readily explained were lumped into dark matter. Dark matter is nothing if not an amalgamation of unexplainable observations. So while dark matter is unnecessary to explain galaxy rotation curves, it is still somehow useful to explain unrelated observations.
> it isn't a band-aide fix
It really sort of seems like that: can't explain an observation, so invent something out of thin air to explain it. Honestly, an hypothesis that elves are causing the observations has just as much validity (or lack thereof). Now, elves have not been proven to be the cause of these unexplained observations, but neither has dark matter.
> the foundations of the concept of dark matter are fairly reasonable.
See above concerning galaxy rotation curves and endnote. Please understand it is quite possible that dark matter does not exist. The reason why it seems like accepted science has to do with scientific paradigms. Once a notion becomes an accepted part of the science paradigm, it takes years if not decades after disproving it beyond all doubt to dislodge it from the paradigm. If science has a problem, it is paradigms.