I guess the demos would be better for Steam as they don't lose credit card fees.
"We will not be granting a refund at this time. The date of the purchase exceeds 2 weeks (our refund policy maximum)."
How much was the game in this anecdote?
Yea, I tried to take advantage of this when I picked up Stellaris, but that's not a game (I don't think) that you can evaluate in 2 hours. I gave it a couple of stabs, but found it just way more complex than I was interested it. I obviously played it more than 2 hours, and they wouldn't refund my money. No harm, no foul, but for some games, 2 hours isn't enough.
MS Flight Sim comes to mind. Apparently game content is downloaded in-game, and it's in the region of 120GB, so many folk blow through 2 hours before they even get to play the game.
I can see this being useful to fill up a steam cache though, depending on how it works.
Therefore this doesn't really change much when it comes to realization that the game sucks very early on.
I suppose there is some small risk difference between "play 90 minutes for free, then decide to pay" vs "play 120 minutes for full game price, then get it back". But in my experience and from what I've heard over the years the refund policy is reliably honored.