This change is a usability regression, plain and simple. Microsoft has replaced a clear interaction cue, the dropdown arrow that told users "this cell has a list", with a Copilot icon that signals nothing about data validation. For anyone building spreadsheets programmatically or maintaining shared workbooks, the practical result is the same: people no longer know, at a glance, that a cell offers choices. That is not an upgrade. It is a loss of information.
The user's testing is instructive. Two different Node.js libraries produce the same behavior, which points to a UI-layer decision rather than a file-format issue. The dropdown arrow still exists in the data validation logic, the list is still there, but the visual affordance has been suppressed in favor of Copilot's icon. This means every workbook, whether generated by code or built by hand, now hides its dropdowns unless the user clicks into the cell. For power users who rely on scanning hundreds of cells, that extra click compounds into real friction. For less experienced users, it creates confusion: "I thought this cell had a list. Where did it go?"
Microsoft has not explained whether this is intentional or a side effect of how Copilot's icon occupies the hover space. Either way, the company should provide a way to restore the dropdown arrow visibility at the workbook level, not just per user. The current design prioritizes Copilot's presence over the user's existing workflow. That is a choice that treats AI integration as more important than the core spreadsheet interaction it replaces. Workarounds like adding conditional formatting or in-cell text hints can help, but they are patches for a problem Microsoft created.
Our view is straightforward: Copilot should complement data validation, not obscure it. If the AI icon must appear, show it alongside the dropdown arrow, or let the workbook author decide which one takes priority. Until that changes, anyone generating Excel files should plan for user confusion and add explicit visual indicators, colored fills, data bars, or notes, to make dropdown cells obvious again. The tool should serve the task, not compete with it.