Depends on what rule book you're using :) Ghost pieces default to `on` in Guideline Tetris.

I think that today we're just admiring the custom paint job on an old commuter car, and not the design of the car itself.

negative. modern tetris has moved way beyond NES' system. there have been many improvements to the game, like a holding piece, hard drop, the ghost piece you mentioned, advanced maneuvers like t-spins, and most interesting of all (to me) is the improved piece selection [1]. you're probably aware of the tall block meme -- when you need it, it never shows up! well that's been more or less solved.

there's also interesting strategies/techniques like 4-wide [2]. there's a whole rabbit hole to follow...

if you want to try out modern tetris, check out jstris [3]. the skill level people have attained is unbelievable [4], and can't be replicated on NES tetris.

[1] https://simon.lc/the-history-of-tetris-randomizers

[2] https://harddrop.com/wiki/Combo_Setups

[3] https://jstris.jezevec10.com/

[4] https://www.youtube.com/watch?v=y3QmU79Vli8

It's a challenge, but it's an uninteresting one.

I have an official Tetris game. \You can toggle on the show/don't show, though i have only managed to do so by accident.