But that is not a problem caused by the sender of the image as she only forwarded a jpeg shot by the camera in her Pixel 6a camera. Blaming the sender is disingenuous as what else was she supposed to do
I not saying it’s a problem with the sender or blaming the senders phone
It’s just a fact that most modern Android and Apple high-end phones like the Pixel 6a as you mentioned (take pictures by default in very high res) unless you adjust them, which in turn then when you first receive the image in an email client, usually will be slow to initially load untill as I mentioned previously is cached locally.
This is not a bug and the mail client is working correctly displaying it how it was sent. Other mailers may reduce the image resolution or pixel size as you say to fit in, but eM Client doesn’t do that and displays it as the original size it was sent in. You can then adjust it after that how you want it displayed by various options in eM Client as in the link below as previously mentioned.