These kinds of dicussions are really pointless in a forum like this.
Theoretically, if an effective aikidoka were to take on a fighter from another style, the aikidoka would be the winner - we are ready for anything!!
So then, why can't an aikidoka quickly lead/throw/pin/submit/etc. someone in the UFC? Who cares what they train in or for, or how strong they are! They want to strike? Take you down? It really makes little difference, does it? Why play their game?
However, that's not really how the world works.
The argument that we don't train for UFC-style fighting is pretty weak. Doesn't aikido make you ready for anything?
Many questions ... no real answers.