I’m sure Apple’s chips could do better in single core if they were willing to push the power envelope way higher too.
Multi-core is easy to beat, just add more cores until you win. There were already chips that beat the M series just by having way more threads/cores.
(Seriously, they rely on air cooling for Neo and MBA — these chips hit 105deg easily and throttle, intentionally)
Adding a thermal pad to a Neo or MacBook Air gives significant boosts peak and sustained performance; whether in benchmarks or real world video renders; but it also reduces your battery life by a little, as there’s less thermal throttling forcing wattage down.
And no, the battery is not connected to the chassis (heatsink), it doesn’t have increased temps.