"It could be that the greater thermal inertia in a large bottle serves to "slow down" some of the effects of aging a wine"
This is an observation based on numerous but relatively empirical experiments. We could probably extend this experiment to even larger bottles, such as the double magnum, but opportunities are rarer and cost may become a significant barrier. It could be that the greater thermal inertia in a large bottle serves to "slow down" some of the effects of aging a wine. Another explanation could be the lower volume of air present in a magnum in proportion to the volume of liquid. When we know that an excess of air can make a wine age more quickly, to the point of damaging it if the quantity is excessive, we understand how sensitive this difference can be.
To summarize the effect of a large bottle on the aging of a wine, we can say that, compared to the same wine in a bottle, the version kept in a magnum stays younger for longer, keeping a better quality of fruit in its flavors. Conversely, the smaller the bottle, the faster the wine will evolve. Therefore, it is not advisable to keep wine in half bottles for more than a year or two, but to buy magnums for wines that are intended to be kept for ten years or more. It is only necessary to create opportunities to consume them, which implies the presence of several amateurs!