structure_block's block state must be set using {NBT data} instead of typical [block state]

I was trying to run the following command to set a structure block in the "LOAD" state, however it failed.  Here is the basic command I tried:

/setblock ~ ~ ~ minecraft:structure_block[mode=load]{} destroy

I eventually found that this command achieved my goal:

/setblock ~ ~ ~ minecraft:structure_block[]\{mode:"LOAD"} destroy

The block state doesn't matter, it fails when any block state is specified in brackets '[' & ']', and defaults to the "DATA" block state.

The NBT data sets the block state.  Is this inconsistent structure is intended?

These issues were reported as ~duplicates in older versions: 

1. MC-133312
2. MC-102383