Basically - you can quickscope your weapon in a no-scope LR. I can't test if it increases accuracy, for me I only felt a diffirence with a scout. I think the server hosters (or whoever controls the plugins on the server) should tweak the plugin to remove this, if they can.
You can technically quick scope, but as soon as you scope the plugin intervenes and stops it. Its true that you get a glimpse of the scope to aim. However it doesn't matter as people tend to move and jump while doing that LR. Your concern is understandable, but unless you have a fix it would be left as is.