80% leaver in 4v4 games

As the in the Title i have no idea whats wrong with 4v4 but half the games have a instant leaver and the other 30% are people who make 1-2 misstakes and leave…
I loved 4v4 back in wc3 classic but what happened?
Especially new player like 4v4 and this is their first impression of the game i love for over a decade…
Are the new player bring this toxic behaviour?
did the old player changed?
AND WHY THE HELL IS BLIZZARD NOT IMPLEMENTING SOME KIND OF PUNISHMENT FOR LEAVER?

Blizzard should apply a leaver ban system e.g. like in League of Legends…but i fear Blizzard is not interested to any further updates at all.

ask blz to add reconnect system, I dced each 30 games once