I think some of you, the "never ever" comments, especially those of you claiming to do professional editing for a living, are forgetting that most if not all of your tools are fiercely guarded, closed source solutions. Right up to those fancy decks, controls, microphones, cameras, and the cables you are using.
In order to create an equivalent, a decent amount of developers and a decent amount of creativity must be put into an Open Source equivalent of Premiere/Avid/Whatever. It can't have the same name or tout the same-name functions, it can't use the same codecs (in whole or part, most of the time), and it can't interface with decks because the specifications aren't known or are far beyond the financial options of the developing team. This includes the inevitable licensing involved with closed source solutions.
Since none of the proprietary software/equipment manufacturers are willing to facilitate broader use of their tools due to an archaic unfounded fear of 'losing out' - in other words, fearing that they won't make their target profit for the year if they open themselves up to the non-Hollywood crowd - you will not see cross-platform equivalents being developed to their full potential any time soon.
If you want to criticise Open Source for being unfit for purpose, or lagging behind on (your) reality - walk in their shoes for a day. Talk with them, perhaps work with them - they are human just like you.
Once you've done at least one of the above, come back with constructive criticism.