Water is NOT A FUEL, nor is Hydrogen.

Hydrogen is an energy storage and carrier. It takes energy to make hydrogen from water. Lots of it.

then you can convert the hydrogen to water either by igniting it (HICE or Hydrogen Internal Combustion Engine) or fuel cells.

but in no way is hydrogen a fuel source.

You can get Hydrogen by using electrolysis using some other fuel to make electricity.
Or you can get Hydrogen form nuclear reactors. But other than free Hydrogen (of which there is very little on earth... but potentially a lot in space) you must use a lot of other power ( green, fossil fuel, nuclear ) to make hydrogen.

Don't get me wrong, it's a fine replacement for other forms of stored energy (like batteries or capacitors) but it is not a fuel (in the form of H2O). All in favor of using it on trains (as a good example) and, possibly, other forms of transportation where we need a source of stored energy and which do not form CO2 as a result.

Watch the second video - the one with professors at the University of Birmingham

Surely you don't assume that those 2 know nothing about H2? The first one is a youtuber that has figured out how to record stuff and make money.

...doesn't know shit about energy.

Anyone who wishes to represent that hydrogen is a source of primary energy rather than a form of stored energy overwhelmingly made by the use of dangerous fossil fuels with exergy destruction is either a fool, someone trying to sell fossil fuels by rebranding them as hydrogen, or incompetent.

This applies if one is a professor at any institution from Princeton University on down and wishes to represent hydrogen as primary energy.

It is among many of the big lies that float around that hydrogen is "green."

...no one has represented Hydrogen as a source of primary energy!

Disaster averted!

Definition of 'Fuel' from The American Heritage Dictionary of the English Language, 5th Edition

1. Something consumed to produce energy, especially.

Also,

It takes energy to make gasoline or diesel from underground crude oil. Lots of it.

Also,

You can get Hydrogen by using electrolysis using some other fuel SUCH AS WIND OR SOLAR to make electricity.

Hydrogen is a dirty fuel made overwhelmingly in almost every case from fossil fuels with exergy destruction.

A Giant Climate Lie: When they're selling hydrogen, what they're really selling is fossil fuels.

There may be people who are dumb enough to buy into the extremely dishonest marketing lie that "the train ran on water" which is rather like saying a "car ran on exhaust" but most people recognize that if one pours water in a gas tank, one will wreck one's car.

Running trains on hydrogen wrecks the planetary atmosphere, as shown in the link above, and scientific references therein.

All the cheap fossil fuel marketing green washing them as "hydrogen" in the world, every obscene video posted here along these lines to market fossil fuels will not change the laws of thermodynamics.

Of course the best thing about this particular fossil fuels greenwashed as hydrogen ad is that at least the guy claiming he rode a train that ran on water has an appropriately moronic expression on his face. It's the only feature that is not a lie, since it is a concept for morons.

All of the hydrogen hype over the last half a century has done nothing more than make things worse, not that the fossil fuel salespeople and sales bots here give a rat's ass about climate change.

...the video host explained the H2 for that train was made using electrolysis powered by electricity from a hydro-electric dam and therefore involved no fossil fuels whatsoever.

Sure, it's entirely possible to fuel a train with hydrogen created by electrolysis using electricity generated by hydro (or any other "green" source you choose), and these folks have done so.

But there are (at least) two very inconvenient facts for hydrogen boosters:

1. The fraction of hydrogen "production" using these methods is almost completely negligible and will remain so for a long time.
2. Choosing to use the "green" electricity to generate hydrogen, then create electricity again from hydrogen fuel cells, wastes much of the energy (since both electrolysis and fuel cell operation operate well short of 100% efficiency).

It's hard to imagine a stupider application for hydrogen than rail travel, since one could simply build an electrified train line and use that "green" electricity to operate the trains directly.

The fact that such stunts are done supports the charge that the real agenda is to extend dependence on the fossil fuel feedstock that supports most actual hydrogen production. This and the numerous other propaganda videos we are treated to regularly commit much more significant omissions by ignoring the realities of current hydrogen production at scale and the relative thermodynamic inefficiency of turning electricity into transportation work via hydrogen and fuel cells compared to much simpler alternatives.

1. Since we have only just begun to consider Green H2 as a wide-scale commodity in the last few years, of course we have also only just begun to simply produce it wide-scale. There's no reason why that can't be done as needed.

2. The energy used to produce Green H2 doesn't matter any more than the energy that is used to produce gasoline from in-the-ground crude oil does. In both cases, it's all carried in the final cost of production which sets the selling price. And as you might know, there will be a loss of energy whenever any energy is transferred. Even charging an EV loses up to 25% of the energy you pay for from the charger (see: https://go-e.com/en/magazine/ev-charging-losses).

Also, most large Green H2 production plants are planned with their own dedicated Green Energy supply plants so no energy is being diverted from any other planned uses. All the energy is used to create the H2, it is not "wasted".

If the "simpler alternative" to H2 for transportation you are hinting at is to just continue burning fossil fuels, these old anti-green tropes won't convince anyone anymore.

...the more the un-informed population learns about H2 through easy to watch videos like your first one, the more support will build for Biden's efforts to transition away from fossil fuels as quickly as possible despite the rightwing pushback against H2.