Sample data export to a text file only allows a maximum Number of 1 Mio data points für export, thats only about 10 to 42s (depending on rate).
Otherwise you can import a textfile containing half an hour stereo data in 48K without problems.
The reason for the limit is because many text editors will choke on very large files. Nobody likes crashes.
With default settings, 1 million samples of a stereo track produces an output file that is around 18 MB. Exporting as HTML produces a file that is over 100 MB, which is likely to take a while to open, and the web browser is likely to become very sluggish.
If you really want to create even bigger files, and you have software that can cope with the huge files, then the limit can easily be removed by a small modification to the Sample Data Export plug-in.
WARNING: THIS IS NOT RECOMMENDED. PROCEED AT YOUR OWN RISK.
Open sample-data-export.ny in a plain text editor (such as NotePad++).
Change line 13 from:
$control number (_ "Limit output to first") int-text (_ "samples") 100 1 1000000
to
$control number (_ "Limit output to first") int-text (_ "samples") 100 1 nil