Please, don't assume your situation is universal. I'd take this smartphone immediately. I'm never far from a 5G tower. I used to have a speedtest script on my Android before I bought an iPhone, and the average speed I had at any time was over 100 Mb/s. Only 5 days of a year I was below 50 Mb/s - but still connected, every day.
> Just the screen is probably already 20% or so of power consumption even at very low brightness
There are other kinds of displays, some of them don't need any brightness at all, but even those that do are getting much more efficient. An old/cheap IPS is incomparable to what a Samsung AMOLED can do, and they're not stopping there.
I use my phone very often - much more than 5-6 hours of screentime - and display is only around 10% of the power budget. The 5G connection usually takes more as I'm always on some call.
I'd gladly take a phone that's just the same size and weight as Samsung S9, but has a giant battery and mainframe-level performance. I'd gladly pay the price of having to be connected, because I have to be and am connected anyways.