Certainly not my cup of tea, and has been that way since a long time.

Evidently, my personal preference is to minimize the influence that a build has on he inherent difficulty of a a fight, ideally making it so that the player would have an equally hard time fighting against every opponent they will be facing - that's especially important to consider, imho, in light of the fact that most tournament allow only one character in, preventing the player from picking a more favorable matchup if desired, as is common practice in many competetive gaming scenes: pocket characters in fighting games, different loadout picks and team composition in FPS games, both of the above in a MOBA. Alongside with implementing multiple round systems, in which the players have to win more than once against their opponent, this allow for one to both adapt to their opposition's playstyle, strategy - and, pertaining to the topic at hand, negate the influence a bad matchup. It's commonly accepted practice, in other words, and it probably dos make competition more fair and skill-oriented.

Of course, the mechanics of rp fighting are different, the reins of character creation being in the hands of the player. Theoretically, someone with enough knowledge, experience and creativity can come up with an ample character build that allows to be a jack of all trades, master of none, comfortable agaist any opponent. However, the dfficulty of accomplishing that aside, you yourself proceed to say that trying to have the right tool for every matchup isn't the right way to go, which was sort of what i wanted to say: it's the norm to have a bad matchup and the opposite is most likely quite boring and hard to acheive. However with such powerful, make-or-break tools that the current regulations allow for (as far as i see), the difficulty of a bad matchup can get needlessly amplified: getting oneshot because of your character's specific build, in a situation where other competitors could have been much more successful, is pretty vexxing, to say the least, and not very fair. It's the difference between having a hard time and having no time at all to do anything because you get fooken rekt stemroled m8 that i am concerned about.

If you think that my point of view, along with my deductive ability, are bullshit, and that i should rethink my way of life, that's fine. This isn't a practical concern of mine, as said before, and i'm willing to drop the argument entierly if  it starts becoming redundant or sparks trouble.