If the file size is not the cause of too much data, check whether there are any formats in the non-data area of each worksheet. For example, set a border or shading for all rows, or set a border or shading for an entire column. What I know about the soaring amount of Excel is basically the same as this, with unnecessary formatting. Because in order to save trouble, people who do Excel are likely to directly select the whole row or column and then apply the format.

The solution is to select all culling formats, and then format only the data areas that need to be formatted.