My humble opinion, bugs and hackers Game
People who send cards to the graveyard without taking any action, without having more than 7 cards in hand, really suspicious.
People who prevent you from using all your mana while you're doing something and send me to the attack phase, making me lose that mana. I couldn't activate Tyvar, the Pummeler's ability with 10 green mana floating; it jumps me to the attack phase and the floating mana disappears.
People who play a land every turn until the 5th without any problem, with perfect spell sequences, for 5-6 games in a row.
People who take a year to decide to use the only card they have in hand in a winning situation, playing with a slowness worthy of a final with million-dollar rewards or as if they had a gun to their head while they play.
On top of that, this company that makes millions can't fix the bug that makes a white bar appear at the top of the menu when you sideboard in best-of-three. I think it's been around for a while.
At this point, they should just delete Pioneer. Few people play it, it doesn't contribute any revenue to the game, and it's just spammy "thoughseize/fatal push" and "izzet lessons/mono red. 1-2 mana spells spam, who need ramp that days with that stupid level power
I think the game designers failed.