other factors like usage time, intensity of use, and charging habits also have effects on the lifespan, so it's hard to compare one person's experience to a single other persons and draw a conclusion that's anything other than anecdotal without some very specific controls.

what i do know for certain is that the heat generation from wireless charging has been long studied, and so has the effect of those heats on li ion batteries.

https://pubs.acs.org/doi/10.1021/acsenergylett.9b00663

https://www.sciencedirect.com/science/article/pii/S1002007118307536

So sorry about your wife's battery

yep! it's just less efficient than wired charging and whatever is lost in the process is turned into heat, which is particularly poor for your battery. batteries are consumables anyways and it seems like most people get it replaced at least once in a phones lifespan, so it doesn't really matter if you're ok with that. from my experience fixing phones over the years I can definitely confirm that using wireless charging consistently, particularly if you're doing anything intensive at the same time, will lower the lifespan of your battery significantly.

Wireless charging generators a lot of heat. I'm sure I'm wrong, but I thought it had to do with the energy loss from the wireless powershare causing extra heating.

yes! heat is kinda the worst thing you can do to a battery. I'm not a chemist, but I believe the chemical reaction that charges/discharges a lithium ion begins to breaks down when performed in a heated environment, and I can confirm that consistent exposure to heat is how you get the really puffy spicy pillow batteries.