There should be a "category 1" widget under presentation > widgets which is not a cloud, but unfortunately, when it comes to tags, there is only the tag cloud.
The only way to create a straight list would be manually using a text widget, and since there is no tags page or anything, there really isn't any way to get a list other than going through your posts and creating one by hand.
The tags and tag cloud widget should never have been introduced without controls similar to the category cloud widget, and without some way to manage them. A job half done.
A tag list widget similar to the category 1 widget probably would not work since some people have hundreds of tags (I have right at 100) - and some multiple hundreds. That would make for a really long list in the sidebar, but perhaps they could introduce a pulldown or popup tag list widget. Or perhaps a two-column tag list page.
The bottom line is, when it comes to tags, the cloud is all there is.