Ah right, airplane mode makes a ton of difference. I also tend to have it enabled as much as I can, usually when I'm home (and thus reachable through VoIP services) or at work. And I (almsot) never turn it off, I just leave it in airplane mode. I limit the charge to 75/80%, with ACCA, so I get even less juice.
And I'm sorry, I also dislike big phones with huge screens and batteries, there's no real need for that. But I know that you can fit better batteries in smaller phones as well. My previous device was smaller than the Pixel 4a, but had a bigger battery, while having almost identical weight.
I wish manufacturers would make smaller phones, really. I'm very unsure what other device I will get after this one dies or gets broken...