In any case, you should not do without image optimization. When it comes to image optimization, there are a few components that can have a big impact on your website’s rankings. For example, Google is placing more and more importance on websites making their content available quickly.
Page Speed or Core Web Vitals are becoming more and more important and often it is images that slow down the loading of your page. Especially if the images were uploaded in the wrong size, they still have to be compressed by the browser. This is exactly what costs you valuable loading time. Thereby it is easy to compress your own images with free tools without quality loss.
If you want your images to be found via Google Image Search as well, you can also provide an image sitemap. This gives the crawler more information about your images and possibly crawls images that the bot would not have captured before.
Also, markup with semantic HTML helps the Google Bot process your images better, as CSS images cannot be read.
To refresh your knowledge of image optimization at this point. Google only supports images in BMP, GIF, JPEG, PNG, WebP or SVG format. Also, Google uses image URL and file names to understand the images.
The alt text is used to describe the image to users who cannot see it. But the alt text also helps Google understand what’s on it. Therefore, this should also be optimized only for this.