I've worked at companies where soft delete was implemented everywhere, even in irrelevant internal systems... I think it's a cultural thing! I still remember a college professor scolding me on an extension project because I hadn't implemented soft delete... in his words, "In the business world, data is never deleted!!"
No comment from the professor on modifications though?
But... It's true. Deleting data completely is an easy way to gimp and lobotomize your future analysis.
Storage is cheap. Never delete data.