Why can't RC circuits oscillate in frequencies higher than RLC or LC circuits?
Passive RC filters have no frequency limits but may have some L, C parasitics.

A resonance within the gain bandwidth limits of an active inductor using  with a negative impedance converter (NIC) cct.in an Op Amp or video amp is possible without an L.

e.g. LC passive filters and Microwave Circulators, isolators with passive NIC waveguides.  

The practical limits of ANY passive parts are specified by parasitic values and Q at some test frequency. 

Parasitics are the other 2 variables out of 3 for RLC, because every passive component has an equivalent Rp-L-C-Rs value or more.