Hello Anthony,
Yes, not everything is going to be right for every individual on the new website, but the team have worked hard over the last months and discussed the various options and tried to implement what we we best.
You'll appreciate that we are not going to make immediate changes on one person's view - we need to get an idea a range of feedback and consider the implications. It’s not set in stone.
There is a bit more depth to the point you raise. Yes, there are decent advantages for members to edit old text. However, some significant disadvantages too. For example, someone could render a useful thread meaningless with bad editing or simply a grudge. Some members might like to see how a discussion flows and adapts over the weeks, and it's stays accurate record of whats happened - personally I would prefer that, but I'm not wedded to it.
There is a balance here, and it needs more than one view.
OldAndrewE - yes, moderators/admins can change content on the site.
Simon