The hivemind and Google leads to the answer immediately.

There is an undocumented setting

set excelxlsxlargefile on

which will allow -import excel- to bypass the size checking. But Ricardo should be warned, the library we use to import Excel files has a large memory footprint when dealing with large new xml based xlsx files. Also the library currently has no ability to allow user to break during the middle of loading an Excel file. Hence if Ricardo’s do file attempts to load a large Excel xlsx file, his Stata session will become unresponsive until it finishes. During this time, Ricardo will not be able to break out using the break button.

Source: Re: st: import excel-file too big