This question from a Reddit user, asking whether Excel can sum cells based on *when* the data was entered, is not stupid. It is a sign of something broken.
The person who posted this knows what they want: a running monthly total of values they typed in January, then February, without having to manually tag each entry with a date. That is a completely reasonable request. And Excel cannot do it. Not natively. Not without workarounds that require you to become a part-time programmer. You can write a VBA macro to capture timestamps, or you can manually add a date column to every row. But the spreadsheet itself has no native memory of when you typed something. It treats your January data and your February data exactly the same way: as static numbers in cells.
This is the gap that AI-native spreadsheets exist to close. A tool that understands context, when data arrived, where it came from, what changed, is not a luxury. It is a productivity breakthrough for anyone who tracks inventory, logs expenses, or manages project timelines. Instead of forcing you to build scaffolding around your data, the tool should recognize that the act of entering a value in January is meaningful and can be queried. You should be able to ask: "Sum the cells I added last month," and get an answer.
The user who posted this question deserves a better answer than "use a helper column and a formula." They deserve a tool that treats time as a first-class property of every data point, not as something you have to retrofit. That is the direction we are heading. And it starts with admitting that the old way, chasing dates across static cells, is not a skill you are lacking. It is a limitation the software should have solved years ago.