I agree the landing page is confusing though I believe it's called waffle.io because kanban cards create a grid pattern & waffles also have a grid pattern.
As a verb waffle has the same meaning in American English but the images of waffles on their landing page make it clear they are going for the food. For me at least it's easy to not jump back and forth between meanings of waffle once I understand the intent is to refer to the food.
Homonyms can be confusing but it helps when such a stark difference in meaning makes it easy to distinguish what meaning is appropriate in a given context.
