If you have an extensive template, it could be a mess.
The Attribute number of the linetype, as well as the type of line it is (dashed, symbol...) determines where it sits in the drop down menu.
You would have to clear out your linetypes in attribute manager, and bring them back in the order you want to view them. This still doesn't fix the issue of them be auto-sorted by line type - solid lines at top, then dashed lines, then symbol lines.
If you are trying to place a symbol line up top, and you have a lot of dashed lines, the symbol line will still be placed after the dashed and solid lines even if the symbol line attribute number is (1).
Overarching all of this is the fact that deleting all the linetype and reinstalling them in a specific order will mean any predrawn details using those lines will be redrawn with whatever new line is using the attribute number previously assigned to the line it was using.
Hopefully someday we get the ability to edit these attribute numbers, it would solve many other problems as well....
AC 6-26 - Intel i9-9900K - RTX3090 - Windows 10 - 64GB RAM