You know what? I'm going to say it: this Let's Play thing isn't as black and white as you want to believe. While I'm not entirely on Phil Fish's side, the very idea that Let's Plays should count as "free advertisement" and with some people saying that the developers SHOULD be paying Let's Players reeks of con artistry. You sound less like a passionate person and more like the guy who washes (badly) car windows during a traffic jam and then demand payment because you did a "service." In fact, giving the gaming's entitled attitude about the entire damn thing (though, to be fair, Phil Fish's attitude didn't help much), perhaps we should finally bring this issue to the courts to see whether your meager excuses hold up to the actual law.
That being said, I'm not against Let's Plays themselves nor am I saying that they shouldn't be paid. I will say however that it should depend on the developer to decide whether or not they will allow it. The main reason is because, unlike a review, critique, or even a short preview, a Let's Play usually entails playing a game from start to finish with little to no editing. And yes, before you even ask, as someone who has done Let's Plays, I am fully aware of the time it takes to make one. But unless you are making Let's Plays in the style of ProtonJon's Superman 64, you're not doing that much work editing.
Now, before I tackle the reasons people are going to counter my argument with, let me say that I am only talking about Let's Plays. Reviews, Critiques, and previews could fall under Fair Use given the past with books, movies, and other media forms. Now, the definition of Let's Plays is a bit loose but for the purposes of what I'm explaining here, I will try to give a more concrete definition. A Let's Play consists of a few things:
* A video game is played over a video or group of videos from the beginning of the game to the end.
* The video game is being commented on by a person or a group of people
* There is little to no editing involved to show as much gameplay as possible.
Now, given this definition, some Let's Plays (like Minecraft and the before mention Superman 64 Let's Play by ProtonJon) don't fall into this definition, which is why I say that this thing is a grey area. But for the purposes of this discussion, let's concentrate on the ones that follow this definition (which is the most common type of Let's Play anyways).
The first counterargument I see here is that Let's Plays are a transformative work, as such they fall under fair use. Because no people can play it the same way, watching someone play a Let's Play would be inherently different than playing the game itself. Now, there are a few games (Minecraft, Terarria, and Starbound to name a few) in which this argument has merit. However, I would argue that not all games (and indeed, the majority of them) can make good use of this excuse. Games like Visual Novels (Ace Attorney, Professor Layton), many JRPGs (Project X Zone, Final Fantasy XIII), and story driven games (Wolf Among Us, Walking Dead) involve very little gameplay and focus more on the story to convey its worth. If I can watch these on Youtube, it can be argued that these could substitute actually playing the game. As for games between sandbox and visual novels, there exists are large grey area. Arguments for both sides can be made which is why I said that it should be up to the developer to decide what he wants.
The second counterargument I see is the "free advertisement" excuse. Which, I'm sorry, is not an excuse at all. It really is like me saying that because I told everyone in my town to buy a Wii U, Nintendo should pay me money helping them sell. After all, I'm freely advertising the game. Furthermore, if you really wanted to argue that you were doing a free advertisement of the game, could I then counter that if you did not do a good job Let's Playing or even used the Let's Play to criticize the game, I could demand reparations for doing a bad job advertising my game? Could I hold you accountable for failing to advertise my game properly? Do you see how big a slippery slope this excuse is? There are other reasons why Let's Players should get paid that can be debated so can we just stop picking the one that can be broken into a million pieces within the first two minutes of a court of law?