Pro SEO Question: SEO Difference between image WP Alt-Description and image EXIF Data

Hi guys
Simple question, but I guess tricky answer that need a bit deeper SEO experience:

It's no question, Alt-Description and some EXIF data makes sense for image SEO:
https://www.colorexpertsbd.com/blog/exif-data-on-image-seo-and-various-platforms/
https://developers.google.com/search/docs/advanced/guidelines/google-images

BUT what I am confused is:

In Wordpress I can choose a alt-description for an image which will be embedded in the HTML source text. So google will read this and gets the useful image metadata (Al Description) for an image search.

Does it make sense to add further EXIF data to the image itself? So Google will have two sources for the image metadata: The Wordpress HTML code and the image EXIF information. But does Google actually take both values into account? Somehow, as a strange example, this image EXIF Alt-Description could be different from the Alt-Description in Wordpress, eg JPG Meta EXIF Data "white circle on black background", Wordpress Media Manager Alt Description "red square on green background".

Does the google image search indexes both information, the Wordpress Alt-Description (and further Wordpress image Metadata) AND the image EXIF data or does is it enough to just use the Wordpress Alt-Description.

The negative side of image EXIF metadata with SMALL images is, that their filesize can be blown very much up, this effect can be extreme: Instead of 8 kb (without Exif Data) its >40 kb with Exif Data. It is therefore important to weigh up which advantage predominates: the text information or the small file size.

I could try to find this out, but it would need a bit of time, so I try to ask here this interesting and important image SEO question.

Thank you for your answers and opinions...
Dave Buettler-Avagyan, Luzern, Switzerland