Back in the Nokia brick days you could easily go a full week between charges.

Of course it's an apples to oranges comparison since a modern smartphone has infinitely more functionality, but in this one thing modern phones remain objectively worse.

You can still go a week on a modern phone if you restrict your usage to what you would do on a Nokia brick phone.

Does it, though? Unless you go back so far you're talking about fixed–layout b&w LCD screens, the next era after that had games and the internet — what's actually new since that time? Multitasking yes, what else?