GoKawiilFirst up, the pros of dropping fans from the MacBook Air. The big one is obviously a complete absence of fan noise. If you've ever owned a powerful gaming laptop, you'll know how hugely distracting constantly whirring fans can be. With newer MacBook Air models, you're guaranteed a whisper-quiet experience even when your machine is under heavy load.
No fan means the MacBook Air is lighter, too. Just compare and contrast that last Intel model with a fan to the MacBook Air M2. The 2020 Air weighs in at 2.8 lbs, while the latter tips the scales at 2.7 lbs. With the fans now jettisoned, Apple has also been able to boost the battery life of the last few iterations of the Air. Though laptop fans don't traditionally consume a ton of power, dropping them has slightly improved battery performance.
As for the cons, the most significant downside revolves around thermal throttling. If you're a high-end laptop user, the MacBook Air often isn't an ideal choice. That's partly down to thermal throttling, a process whereby macOS down clocks processor speeds to keep temperatures to reasonable levels when the CPU is under heavy load. By reducing processor speeds, performance subsequently drops. In real-world terms this will manifest as longer video exports or dropped frames when playing games. Without fans, the MacBook Air can also run noticeably warmer than older models, with the likes of the M5 Air often feeling particularly toasty on its underside during heavy loads.