Board Thread:Support Requests - Getting Started/@comment-40017802-20200820003755/@comment-1038387-20200820045853

Leave the deleting to admins, you can at most blank a page, which is not the same.

You were indeed blocked by an AbuseFilter, this one prevents mass removal of text by new editors. They have some pretty strict filters from the looks of it designed to combat one particular user in the past.