I am building an app to filter to exclude status = Draft.
I use this formula
but turns out it has delegation warning on .Value <> Draft
I checked on my other apps, it was not a problem there
Any idea why this happens?

Hi,
The ReqStatus.Value is a Choice column, which is considered complex in Power Apps. As a result, many functions, including In, Not, and <>, are not delegable operators in SharePoint. This is a common pitfall, as people often use these operators without considering how to reverse-engineer the filter logic for a Status field.
Typically, you'll have a limited number of statuses, such as Approved, Rejected, Draft, Complete, or Started, depending on your design. Instead of filtering out records that are "Draft," why not reverse the logic and filter for records that match the other statuses?
In your case, assuming you have three statuses Approved, Rejected, and Draft you can filter your ReqStatus column like this:
Filter('Meeting Request', ReqStatus.Value = "Approved" || ReqStatus.Value = "Rejected")