NES Tetris has a weighted randomizer where it is less likely to get the same piece twice in a row (if the same piece is going to be served twice, the second is rerolled one time). So it is possible to get the same piece twice in a row but less likely.
Modern uses random shuffles of the piece order (put all the pieces in a bag and draw random pieces from the bag until the bag is empty).
Modern uses random shuffles of the piece order (put all the pieces in a bag and draw random pieces from the bag until the bag is empty).