I mostly agree with the premise here, but I want to play devil's advocate:
* The game isn't actually reviewed. Maybe you can play the game perfectly well without paying for gems. Maybe the game is actually more interesting to play for the fact that you have to manage your resources according to the time cost/gem count. Maybe there's a genuine reason why thousands of people have given five stars.
* There's no reason to believe that we are supposed to pay for the £70 bundle. Maybe the £70 bundle is just for the IAP 'whales' who are paying for everyone else to play. When I go to a coffee shop, I don't have to buy a triple-cream, triple-chocolate mocha latte for £8, but I also don't need to get annoyed that this is on the menu.
Regarding the high number of five-star ratings, there's a common pattern in this style of mobile game to optimize for ratings. After the tutorial introduces the mechanics, and after a bit of time spent in the main game, it prompts the user to go to the app store and give a rating. Shortly after this prompt is when the game starts hitting the player hard for IAPs. I haven't played this new Dungeon Keeper, but EA's Plants vs Zombies 2 followed this model to a T at release, popping the rating prompt near the end of the first world, but before letting the player know that they would need to replay the entire world repeatedly in order to pass the paywall for free.
The reason people play these games is habituation. By placing delays on things, they encourage you to take the content in small doses, and thus build a habit of playing, rather then burning through the (relatively small) amount of content quickly. Once people have a habit, they will rationalize it... "I am playing this, so it must be fun". Even once the content and new game play runs out and it is reduced to a rote grind, people will continue to play because of the sunk costs creating an unwillingness to abandon all the weeks or months of grinding they put into the game.
It is a model pioneered by the MMO industry, but taken to an even greater extreme, where some of the worst psychological traps that people get stuck in are used against their customers to extend their profits.
There is something to be said for the fact that it's a different game. They took some of the mechanics and IP of the original game, and made a new game, so he shouldn't have expected it to match the original experience.
That said, from what he did review, it seems pretty clear that this new game is up there with the worst of the freemium/IAP model. I think your advocacy veers a little towards being willfully obtuse. I would say there has never been a single game that has been made more fun or interesting by the "wait a few hours or pay money to continue" mechanic. Resource and time management is certainly a valid mechanic but that assumes that the player can continue doing other things (as in actual "gameplay") while the time-intensive operation is happening. Even failing that, if we assume there is some game that is fun to not-play while you sit there waiting, the fact that you can pay money to advance invalidates it as a gameplay mechanic. At that point it can be nothing but a business decision.
On the coffee shop example, you are paying for the intrinsic value of the coffee, so no, other offerings should not affect you. But with the "bag-o-coins" type of IAP, you are not paying for the image of your character holding the coins (i.e. a cosmetic item, which is considered somewhat less evil), you are paying for a means to an end, to continue playing the game.
It would be more like this: the coffee shop advertises free wi-fi, which is one of the main reasons you went there. But by default your bandwidth is crippled to the point of near uselessness, and you have to buy the ridiculous mocha to unlock a decent speed. Now are you annoyed about it?
* The game isn't actually reviewed. Maybe you can play the game perfectly well without paying for gems. Maybe the game is actually more interesting to play for the fact that you have to manage your resources according to the time cost/gem count. Maybe there's a genuine reason why thousands of people have given five stars.
* There's no reason to believe that we are supposed to pay for the £70 bundle. Maybe the £70 bundle is just for the IAP 'whales' who are paying for everyone else to play. When I go to a coffee shop, I don't have to buy a triple-cream, triple-chocolate mocha latte for £8, but I also don't need to get annoyed that this is on the menu.