[Quoth]

No, it's up to you to make sure the image formats and sizes are compatible.

But only use FIXED layout for 10" tablets. It's terrible on phone apps and real ereaders. Actually Amazon won't even deliver a fixed layout to most actual Kindles. It's for the Fire and apps, not real ereaders.

I use the "Tablet" page option on Calibre as that leaves imported image at the original resolution.
The test purchase downloaded ebook from Amazon in mobi, azw or kfx on a wide range of real kindles have been fine from the epub2 upload.

I make sure images work on a Kindle Keyboard, PW3, Kobo Libra 7" (epub), Sony PRS350 5" (epub) and on the Lithium app on a 6" Android phone. Sometimes I check on an an old 5" phone.

I preview in the Calibre viewer with the window reduce so it's roughly like a PW3 or Libra.

You can use an image large enough for a 300 dpi Libra 7" and have it scale, or use a fixed size smaller image. Old ereaders will get very slow if the image is too large, even if rescaled to fit.

In general, ereaders are for text and more than a small image can be a problem. A fully illustrated or pictorial book really needs a tablet.

I'm not impressed with the Kindle Previewer. Calibre is better. Testing on real kindles and kobos and a phone app like Lithium is better.
The Kindle apps on iOS and Android are designed mainly for downloads from Amazon. A 3rd party epub viewer is more use to preview as you upload epub2 to KDP anyway.