Hi!
Airplane mode does initially disable all connections (Wi-Fi, Cellular, Bluetooth) however all except Cellular can be separately re-enabled even if airplane mode stays active. Hence why I asked if your carrier supports Wi-Fi Calling.
Did you update to 14.4 already? Even though the drain bug on my device isn't gone, the overall battery performance though got better. And because I am connected to Wi-Fi 99.9% of the day, airplane mode with Wi-Fi calling works like a charm.
Being on airplane mode and completely offline (in case you do not have the Wi-Fi calling option) is not really a fix either, is it?
I only use and recommend airplane mode because Wi-Fi calling exists and is a possibility for many.
In any other instance, I advise you to plug in your phone however often you can until Apple hopefully fixes this, so you are not prematurely ruining you battery (if it drains entirely multiple times a day and you have to recharge it, it most definitely will put on many many cycles and makes it degrade even faster). But as you said, it is sitting on your desk most of the day waiting for a fix, it's alright ;) The battery draining like this (not only your device, but devices across the entire line-up) has to be a software bug which they should be able to patch up. Nobody knows what is taking them so long, and why they do not address this. It has made quite a bit of fuss already and they don't do anything. Maybe they are clueless as well, who knows