There is no reason why rimfire cartridges should not feed reliably. Thousands, if not millions, of Marlin 60 rifles and Ruger pistols are living proof. A rimmed (although not rimfire) cartridge is the oldest cartridge still in active military service - 7.62x54R.
There are some bad rimfire designs out there, but they are bad because of their designers, not because they are rimfire.
I believe what most jammomatic rimfires suffer from is cheap materials and shoddy workmanship. They generally use more plastic and cheaper and thinner metal, which lead to faster wear and are easily damaged. Even so, the AR-7, when made by an older incarnation of Charter Arms, was more or less a single shot rifle, where the original Armalite ones ran without a hitch.