It doesn't matter if I FE or not. I could have received LSD, finalised upon arrival and tested it couple of days later (happened lots of time) only to find out it was bunk (thankfully never happened). Now we know it's not possible to change the feedback but before the update it was normal in this kind of situations. People are getting screwed with this update, users and vendors. I also learned that SR support is not really a support and that they don't care about users. Even if I didn't FE I couldn't rely on them for any meaningful support.
You are just pissed off because you didn't get the outcome you wanted, SR support does care about buyers and the admins work hard to help resolve issues. When however someone chooses not to use the protection built into the system i.e. escrow then they can't help you.
Re the feedback issue I can see how retrospectively that is going to catch a few people out who FE'd before the change. However in future if you do decided to FE just bank the feedback, click out of the page without leaving any and it will stay sat in your order section ready for when you are ready to leave it, you do not have to leave feedback at the point of finalization if you choose not to.