I believe this can relate to any art form. There will be no success, because there will always be a progression and creation of joint combinations and moves, which indicates that there is no initial success at the end of it all, because the game never finishes (persay).
This means that every fight will be different and every fight will continue to be had in each room, creating unique opening outcomes and unique challenges for each fight. This means that, even if you consider yourself to be at the Toribash Skill Cap, there'll still be a fight, in whichever mode, that tests your skill, ultimately pointing towards the fact that you still need to make progress in whatever areas "tested" that skill.
I say no. A Toribasher's journey to greatness is much like any Martial Art. Jaker may be our Bruce Li, but I bet you both of them continued to perfect their skill sets every day without fail, even though they practically knew they were the best. Tis an infinite progression, in my opinion.