iPhone 12 battery draining fast

That is simply not true, I'm an engineer working in the mobile telecom industry and the discharge rate currently seen on my iPhone12 is a faulty curve. I feel no point in debating that, as this is just a simple scientific observation that I already cross-referenced with a known-to-be-good situation both both the iPhone11 and the iPhone12 under normal conditions.

Please check both curves, on the top you can see a drain, regardless of any handset usage during day OR night AND despite low-power mode. Any engineer can tell you this is abnormal behaviour. On the bottom you will see a 'normal' discharge curve, where you can clearly see it's not a straight line down the hill but is depending on usage etc. Note: both are made on my iPhone12Pro, the bottom one differs in 1) no second 5G SIM (in 4G mode only) enabled and 2) low data mode mode enabled on the first primary eSIM. I'm currently testing to see what actually caused the difference in discharging by disabling low data mode on the first eSIM. If the discharge rate continues to be 'normal' then there is a clear indication that enabling the second SIM caused abnormal behaviour. That is not 'me too', that is just a normal observation. If you think it's normal then you're perfectly entitled to that opinion, but then there is little you can contribute in this topic I'm afraid. It is my personal and professional opinion that this is not normal and considering the fact that Apple has accepted bug reports, fixed the issue and contributed them to me in the release notes I think I'm still doing a useful job here :-)