When you are not able to open large file, only providing the option to open in Excel, please also provide option to download the file.
When you are not able to open large files, provide and additional option to download the file along with the open in excel option.
John Collard commented
Yes, this is important because (at least at my organization), the option of opening in Excel does not work correctly. So then the person to whom I sent a link to the file has NO WAY of opening or viewing the file.