Just because something or someone is successful doesn't mean all decisions that are made are optimal, close to optimal, or even not an active detriment.
The famous example is people conflating Steve Jobs being an asshole with being successful.
The famous example is people conflating Steve Jobs being an asshole with being successful.
And here, it's not even the case of all those weird nerds complaining about missing headphone jack. Go poll normies about screen sizes. Regular people complaining about phones being too large is pretty much a meme now.
(Engineering-wise, phones do get thermal advantage from the current form factor trends - thinner but larger -> more surface area. But I suspect it's more than compensated by the extra heat from the larger screen.)
Those are the revealed preferences of millions of customers. How many people did you poll?
You aren't calculating the effect of phone size correctly.