From: #245

Page: https://wordpress.org/blocks
Heading 2: Build without limits

1. Can probably remove the ALT text on the block icons. They are decretive and do not add value to the content. For example, Paragraph icon, Heading icon, etc. these do not tell users much or increase context in a meaningful way. If empty ALT is not optional, they can be left as is.
2. I think a list presentation for these blocks would be better so that way screen readers get contextual information about how many blocks we'll be calling out here. It could be in a standard <ul> or <ol> if the numbers are not distracting.