Deleting text and using strikethrough are not the same. Deleting text simply deletes the text. The audio behind the text remains in tact.
Using strikethrough has multiple benefits. Strikethrough removes underlying audio in the following scenarios:
When you export audio with strikethroughs removed
When you export text with strikethroughs removed
When you playback the file in the Sonix editor
When you use the EMBED function to display your transcript in the Sonix media player