Larry is a great dude. Really knows his stuff, and in-person is one of the most easy going dudes ever.
The video was kind of dumb, but proves the point: dry is even dumber. The only reason the video is kind of dumb is because the claim of over-lubrication has to do with stuff sticking to it (like you said), but the vid never addresses that really.
The bigger problem with lube is what people use. The military issues CLP, which when it gets old will become stickier than it needs to be. Regular 10w30 will work great in almost every firearm, and rarely will it attract junk that can cause an issue. There's only a few that require specialty greases, but us peasants don't get to own them anyway (MK14's and M134's are top of the list for 'specialty' lube). Even in those cases it's been found that more is always better. Forgotten weapons (Ian is another great member of the gun community) has done plenty of
informal 'mud tests' that show the concerns about debris ingress on an AR are mostly overblown.
Dripping oil is really only inconvenient, it never hurts operation (unless maybe it splatters your optic or NVGs). Too little will jam a gun in a hurry. If you over-apply, the gun becomes damn near self cleaning! Unless suppressed, then you're dealing with sludge no matter what...
The problem with the AR market is that lots of companies advertise 'spec' stuff that just isn't, because it has a 'mil spec coating' on a junk part. MIL-DTL-16232 is technically 'mil spec', but is just phosphate and doesn't make a trigger the proper hardness, material, or even ensure that it complies with the x-ray requirements for MIL castings. Sadly, there's few ways for the general public to find out 'how close' to spec their purchases are except to buy from good sources.