that is not the current state. For SEO purposes, images should have a title tag. Please see i.e. https://de.onpage.org/wiki/Bilder_SEO.
You may re-read that page. The only place where a "title" is mentioned is
Title-Tag: Auch der Meta-Title sollte verwendet werden, um ein relevantes Keyword unterzubringen.
The term "title tag" usually refers to an HTML page's title as in
Nowhere do they mention an HTML attribute for an
img element as in
<img title="An oak tree" alt="An oka tree" src="images/trees/oak.jpg" >
As far as I know this
title attribute would be snytactically wrong. An image uses the the
alt attribute. And the page you linked to doesn't tell any different.
Sorry to insist, but according to the syntax an HTML
img element is not supposed to have a