What does "topline issue" mean in a business and other context that neither refer to gross sales or revenue, nor allude to anything related to a company's income statement?
A reference to the gross sales or revenues of a company, or an allusion to a course of action that increases or reduces revenues. The "top" reference relates to the fact that on a company's income statement, the first line at the top of the page is generally reserved for gross sales or revenue. A company that increases its revenues is said to be "growing its top line", or "generating top-line growth".
This contrasts with net income (or net earnings per share), which is usually the bottom line of the company's income statement.