Alternative text is vital for better websites. It's important for good user experience and SEO.
As wonderful as your images are, some people will never see them. Some people browse your websites without their eyes, using screen readers instead, whether by choice, or by necessity, there is a growing number of people who listen to your sites. If your images don't have helpful alt text they will miss important bits of information you are providing.
Some people won't see your beautiful images simply because they don't load.
Search engines check the quality of your page, and one of the key markers is the accessibility of the site.
Writing a good alternative text for an image can be time consuming.