Ban rate has never equaled overpowered. Rengar was one of the most banned champions in the game for 3 seasons and nobody thought he was overpowered. Just annoying to play against but he had clear weaknesses just like Malzahar does.
Zemaxs has a point. New Malzahar isn't OP in the slightest. I've already played it a few times and he has defining weaknesses. Sure, his voidlings do a lot of damage but that's honestly about it. The rest of his kit feels so weak because they gutted the numbers on the rest of his kit (you know that they took 100, yes you read that right a HUNDRED damage off his E AND nerfed the ap ratio on it in this rework right?)
It's disappointing really. Malzahar isn't even on the same page of how strong Fiora was in this comparison. OP has a point though, Riot will do their typical nerfing as seen in the past. Usually goes in this order.
Step 1. Rework balanced champion that nobody plays
Step 2. "Rework" = overload a champion's kit with unnecessary abilities and numbers that they don't need
Step 3. Champion is either strong or completely broken tier and is nerfed in the first week regardless because Riot looks at only ban rates to decide who gets nerfed and who doesn't
Step 4. Riot nerfs things about a champion that isn't going to address the issues with the champion's overloaded kit like nerfing their base stats, raising mana costs, etc.
Step 5. Riot does this for about 3 patches before finally addressing the real issue.
Step 6. Riot nerfs the issues with the champion and makes them balanced
Step 7. People still ban the champion and Riot thinks that they need to be nerfed more so they nerf the previous "issue" in the kit for the next 3 patches
Step 8. Champion has a 40-45% win rate and now they're picked even less than they were prior to the rework except now they're complete garbage.
Tell me this isn't true and that this didn't happen with Darius, Mordekaiser, Garen and Skarner. Remember that update? The juggernaut update? Yeah those 4 champions are between absolute garbage and un viable. Then we had the marksman update which made Kindred broken beyond belief with the item buffs and same with Graves. They're still getting nerfed to this day. Eventually Riot will nerf Graves's bonus armor he gets from his E and nerf Kindred's damage from her hunted stacks and then you'll never see those champions played ever again.
The marksman update almost balanced out the adc's that they reworked but now Kog'maw, Quinn and MF are never played.
Face it. Riot has no clue how to balance champions. They are always nerfing and buffing random shit to attempt and keep the game interesting so random picks will come up in LCS and get them more views and thus more money from people buying the champions to play them. This game will literally never be balanced.
tl;dr Riot's balance team is high and Malzahar will inevitably be nerfed in a few patches from now for 0 reason