I think going by Flea's checklists (which is a sticky thread) is what's mostly needed.
While it's true that sometimes there's a mismatch between real-world manuals/procedures and the flyables we have in the sim, for the most part the published checklists work fine.
The only notable exception is the Blenheim but there's a dedicated thread for that in the gameplay section covering pretty much everything. In short, you can follow the manual for that too as long as you don't go over +4 PSI boost or 220C cylinder head temperatures (whichever comes first).
I think the only flyables we are really in the dark about are the G.50 and Br.20 because we haven't seen an English language manual for them yet.
Other than that getting Flea's checklists, reading the sticky FAQ and browsing through the Blenheim thread, one has everything they need to know to fly the majority of aircraft in the sim.
Video tutorials are nice but due to the complexity involved it's a pretty big task to do them well and cover all possible scenarios: people stick to text because it's faster to type a paragraph about what makes an engine break, rather than
1) make a custom mission in the FMB
2) fly it
3) record it
4) do the necessary video editing (file compression, voice-overs)
5) upload to youtube
and it pretty much gives the same amount of information. Mind you, that's just for one part of the tutorial, the same thing would have to be done for more than a few different video clips showcasing other parts of the aircraft behaviour, before stitching them all together in a single tutorial video.
Don't get me wrong, it would be a wonderful resource but i can understand the reluctance to pick up such an undertaking. I've thought about doing a couple for a while and quickly gave up on the idea due to the amount of time it would involve. That is, if i wanted to do it right and come up with something that would substitute most of the written documentation (community-made or otherwise).
Then there's another issue as well: updating text documentation is much easier when things get corrected in patches, for video tutorials it would be a case of redoing significant parts of it all over again and mixing them in with the previous version of the video. It doesn't make sense to do them until certain features in the sim get finalized, unless someone is prepared to spend a great amount of time on them over the course of several months. It's almost bordering on a full-time job
