Thing is it is to easy to run away when interdicted. If you buff them to much then you kill piracy as you won't be able to stop someone from running ever. It makes sense that trade ships be more fragile as it is a trade off for what they can carry.
You're forgetting wings, already even traders with armed escorts or do gooders jumping in to help are often overwhelmed by pirate wings. Of course full wings of traders even anaconda traders can be outmatched and outgunned.
beyond that most pirates operate in ships larger than Cobras and adders, most are in at very least an asp, clipper, dropship, FDL or Python with a few bringing extra muscle in the form of a combat conda.
no trader stands even a shred of hope to escape a conda/FDL combo on their own or in a trade wing. And let's face it besides the warp aspect of wing trading what reason would you really wing up to trade in?
Winging up in a trade wing makes you twice as likely to get pulled over. As some pirates like the challenge or want an all you can scoop buffet.
you get an amazing 5% bonus off of the profits which is insulting for the amount you lose waiting for the other person to hurry up.
your jumps are staggered so you have to wait at each jump for your buddy to catch up unless they route themselves but then what's the point?
if you manually take a wing beacon or lock on to the wingmate in front of you you get dumped 20km from the station, how is that useful?
added defense against pirates? As mentioned above any ship outfitted for trading stands no chance against a combat burst centric pirate wing.
traders need more now than ever before a buff to their defensive capabilities because it's often a 1V2-4 scenario and even if those numbers are fair again it's 0-3 combat ships in your wing vs 1-4 in theirs.
