While I personally want a fan and see it as price to pay for better thermals, the disadvantages aren't just noise.

The most critical issue would be the fans still spinning to cool down the machine when it was sent to sleep. That creates the vicious cycle when bagged right after sleep, where the fan try to lower the temp, but their running in a closed environment warms the confined air, which pushes the fan to run faster yet.

That's the recipe for a hot and dead battery when you take it out of the bag.

I had that with MacBooks and Windows laptops alike.