Rocket league uses bracket reset but ill try to explain it.
Throughout the playoff bracket, each team essentially has 2 lives. Lose a match = lose a life, and your sent to lowers. If you lose in lowers, you lose your last life and exit the tournament.
Since the Grand finalist via upper bracket hasn't lost a life yet, they still have 2 lives. Of course the grand finalist via lower bracket is on their last life. If the lower seed wins the series, then both sides are on 1 final life. The teams play another series, called "bracket reset". This determines the winner of the tourney. If the upper bracket finalist wins the first series, then a bracket reset won't be done
The idea is to have the virtues of a double-elim bracket to pertain to all the teams and matches, even if you made it to GF without losing.
I doubt riot would ever add bracket resets to vct cuz bo5 are super long and multiple full length series's between the same teams would tire out players and fans