That is a good question. I do not know what constitutes a "pro-level" NLE from "consumer". It may have,in part, something to do with available codecs. PD cannot read/write Pro-res or DVCPro50, or DNxHD, others. Many companies do not allow for plug-ins, or limit them to LE versions. It can be hard to say PD is Professional when you look at the huge collection of amatuer junk on the Directorzone. And perhaps some of the PD interface can be made to look more "adult". You have to look at what you get for the money, too. There are extra costs to using pro codecs for commercial reasons and that may be in the license.
I'd like to hear other opinions, thoughts on this because as you note, PD is fairly robust.
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