How come I see so many recent videos online l, just Google them. Perhaps they're trainee pilots, so I'll have to wait my turn. They're great learning tools btw as well. And I'm glad you fully qualified pilots appreciate why we're so keen. Perhaps I'll ask cabin crew really really nicely!!
These will all be filmed and posted by pilots from the flight deck. There's no way you'll be able to get on the jump seat during flight, it doesn't matter how nicely you ask the cabin crew it just isn't up to them. As a pilot, I'd love nothing more than to share the flight deck experience with a wannabe, as that's exactly how I ended up wanting to be a pilot in the first place, but the laws simply do not allow it.
The best you'll get is to see the flight deck on the ground, either asking before or after the flight to say hi to the pilots, again I love the rare occasions when this happens and we are usually very accommodating. As for filming in flight, fine after take off, and if you insist on filming anything during take off or landing then do so very discreetly, or the cabin crew will get straight on you, it's their job. Funny thing is the pilot is probably up front with his phone on, tablet on in his flight case, and taped a camera to the window to film the flight.