Some heroes are not allowed or have limited talent choices in ARAM. Why does Gazlowe have access to bomb toss at level 20 in ARAM?
ARAM is won/loss on whom commands more AoE effects. Triple stun circles every 5 seconds is completely dominating in ARAM. Can this be turned off? He has other viable level 20’s for ARAM. Bomb toss is just GG.
Play Deathwing. Problem solved.
But more seriously, when something is removed from the game, it is generally because there is no counter play. For example, Lava Wave is banned from one lane maps because the normal options to counter it aren’t available. You can’t push a different lane, and you can’t protect your minion wave.
AoE affects do have counter play. Don’t stand in them, use cleanses (I can’t tell you how many times I have seen heroes with cleanse options never take or use them), flank or dive their back line, or if you have nothing but single target damage, pick one and blow them up.
While certain heroes are certainly more annoying to face in ARAM than others, none of them are automatic wins.
A lot of heroes have such AoE. Junkrat is a good example where between Endlessnades and 50% bigger AoE at 20 it becomes a real paint. Or Azmodan which literally gains bigger AoE on orb at 20 (because quest is almost always completed by then…).
Ironically I think the issue with Bomb Toss is that all of his level 20 talents are very strong. Mecha-Lord turns him into quite the tank and DPS machine. Miniature Black Hole is the perfect combo tool if your enemies are gathered as escape is less likely and its cooldown reduced. It’s Raining Scrap is perfect for additional turrets to ruin the enemy’s day such as blocking skill shots. Bomb Toss giving bombs just fits right in there.