gdal_translate creates images that are mirrored

The .xyz file is sorted in an unusual way, X ascending and Y ascending. Most GDAL drivers can handle that orientation by flipping the image internally. Thus the "upper" and "lower" coordinates are flipped too:

Driver: XYZ/ASCII Gridded XYZ
Files: test.xyz
Size is 500, 2
Coordinate System is `'
Origin = (715000.000000000000000,6575000.000000000000000)
Pixel Size = (10.000000000000000,10.000000000000000)
Corner Coordinates:
Upper Left  (  715000.000, 6575000.000) 
Lower Left  (  715000.000, 6575020.000) 
Upper Right (  720000.000, 6575000.000) 
Lower Right (  720000.000, 6575020.000) 
Center      (  717500.000, 6575010.000) 
Band 1 Block=500x1 Type=Float32, ColorInterp=Undefined
  Min=28.452 Max=31.080 
  NoData Value=0

If you sort the .xyz file by X ascending and Y descending, the metadata appears in a logical way:

Driver: XYZ/ASCII Gridded XYZ
Files: testsort.xyz
Size is 500, 2
Coordinate System is `'
Origin = (715000.000000000000000,6575020.000000000000000)
Pixel Size = (10.000000000000000,-10.000000000000000)
Corner Coordinates:
Upper Left  (  715000.000, 6575020.000) 
Lower Left  (  715000.000, 6575000.000) 
Upper Right (  720000.000, 6575020.000) 
Lower Right (  720000.000, 6575000.000) 
Center      (  717500.000, 6575010.000) 
Band 1 Block=500x1 Type=Float32, ColorInterp=Undefined
  Min=28.452 Max=31.080 
  NoData Value=0

Unfortunately, the AAIGrid format is not designed for the first orientation, and noone has implemented to catch this issue by an error message or internally flipping back the coordinates. As a consequence, the header for AAIGrid gets generated wrong:

ncols        500
nrows        2
xllcorner    715000.000000000000
yllcorner    6574980.000000000000
cellsize     10.000000000000
NODATA_value  0

The following data is always linewise from upper left to lower right.

As a kind of hack, you can use gdalwarp instead of gdal_translate to save your raster as tif, and then translate to AAIGrid:

gdalwarp test.xyz 3301.tif
gdalinfo 3301.tif
gdal_translate -of AAIGRID 3301.tif 3301.asc

which delivers the correct header:

ncols        500
nrows        2
xllcorner    715000.000000000000
yllcorner    6575000.000000000000
cellsize     10.000000000000
NODATA_value  0