Susskind writes in
SU-ITP-93-15
June 1993
hep-th/9306069
The Stretched Horizon and Black Hole Complementarity
Leonard Susskind, L´arus Thorlacius,† and John Uglum
"We argue that a phenomenological description of black holes, based on the idea of a “stretched horizon,' which can absorb, thermalize, and re-emit information, is consistent with these postulates."
Note word "absorb." In the case of our future event horizon the re-emission must be Wheeler-Feynman advanced waves in the sense of the Cramer transaction.
Note in this case there is an "infinite" blueshift at the future event horizon absorber for the retarded wave that redshifts back to the emitter frequency in the advanced wave in a self-consistent time loop.
"Although we shall not introduce specific postulates about observers who fall through
the global event horizon, there is a widespread belief which we fully share. The belief is based
on the equivalence principle and the fact that the global event horizon of a very massive black
hole does not have large curvature, energy density, pressure, or any other invariant signal
of its presence. For this reason, it seems certain that a freely falling observer experiences
nothing out of the ordinary when crossing the horizon."

This belief becomes questionable if there is an actual plasma at the horizon induced by the interaction of photons on null geodesics with the virtual particles stuck to the horizon. Same would apply to massive particles on timelike geodesics. The existence of a real plasma would be locally frame invariant. A similar issue arises in George Chapline's dark star model that looks like a black hole to the exterior observers.