As you have said several times, the aim of Darktide crafting system is to have the players collect a lot of weapon to have various options then mix and match them.
But a side effect of this is that we all have an ever growing bunch of weapon that we never use because they are grossly underpowered, not interesting, upgraded until the RNG emporor gifted them with a useless blessing or replaced by a better finding.
Right now we can trade them for some coins but lets be honest, every one above lvl 30 have hundreds of thousand of that money that bearly see any use outside of buying one <20k weapon every two weeks.
I don’t think I have seen an announce about the possibility of trading those weapons for building part (even like 10% of the rarity cost) so we can start cleaning our arsenal for a reason.
And sure it might be use to trad inquisition coin for construct components but the ratio would be so bad anyway.