The editor-only horizontal padding for the block element doesn't appear to be helpful. Removing these styles allows all elements (including those blocks that add .block-editor-inner-blocks when in the editor) to lay out as expected.
@@ -17,7 +17,6 @@
@import "latest-posts/editor";
@import "legacy/editor"; // "Blocks" from the legacy WP editor, ie: galleries, .button class, etc.
@import "list/editor";
-@import "media-text/editor";
@import "navigation/editor";
@import "paragraph/editor";
@import "posts-list/editor";
@@ -1,6 +0,0 @@
-.wp-block-media-text {
- .block-editor-inner-blocks {
- padding-right: var(--global--spacing-horizontal);
- padding-left: var(--global--spacing-horizontal);
- }
-}