There's a 100Wh restriction on laptop batteries imposed by civil aviation, which the 16" MacBook Pro hits, so this is not a problem that can simply be solved with thicker chassis and larger batteries either.

> There's a 100Wh restriction on laptop batteries imposed by civil aviation

This made me curious so I looked it up and found this bit on FAA's web site:

> Size limits: Lithium metal (non-rechargeable) batteries are limited to 2 grams of lithium per battery. Lithium ion (rechargeable) batteries are limited to a rating of 100 watt hours (Wh) per battery. These limits allow for nearly all types of lithium batteries used by the average person in their electronic devices. With airline approval, passengers may also carry up to two spare larger lithium ion batteries (101–160 Wh) or Lithium metal batteries (2-8 grams). This size covers the larger after-market extended-life laptop computer batteries and some larger batteries used in professional audio/visual equipment.

https://www.faa.gov/hazmat/packsafe/more_info/?hazmat=7

No, they’re just burying the most important metric, which is performance-per-watt

That's possible by having a bigger battery

That's true, but do they have much headroom to do that without increasing the watt-hours? I know max size Macbook Pros have been at the TSA flight limit on that metric for ages and that's one reason it never increases.