Delete query does not appear to open space on the SQL Server
Deleting rows from a table does not automatically free up space, unless you happen to delete a large chunk of rows that are stored on the same pages, and every row on each such page was marked for deletion. You would need to rebuild the indexes in order to reclaim the space.
Even if you rebuild the indexes, SQL Server doesn't reduce the size of the data file(s) just because you've removed some data inside the file. The assumption is typically that if the database got that big once, it will get that big again, so why shrink the file only to grow it again later? Both shrink and growth operations are extremely disruptive to normal activity. Please read this thread in full to understand why you want to be very careful about freeing up space on your drive (even on a cloud-hosted server):


Why Does the Transaction Log Keep Growing or Run Out of Space?



Also see:


Why you should not shrink your data files