Destiny - Metacritic Average 77 - Popular opinion = This game is average tripe and not worth most people's time!
Forza 5 - Metacritic Average 79 - Popular opinion = This is a great game, definitely worth a purchase and a major reason to own an Xbox One!
Point being, reviews and metacritic aren't always indicative or reflective of the average consensus. It works both ways mind, see GTA IV.
Forza 5 is worth the purchase of an xbox one? Are you even a serious sim racing fan? Go to any sim racing website ( ofc other then forza dedicated forums) and there are TONS of other sim racers that are considered better then forza 5. PC has a ton of them, Assesto corsa, rfactor, Iracing, RRE, all of which have much better physics and handling modles, plus the general consesous on a bunch of forums is even gt6 feels more realistic. Just take a look around the web, you will see what i am talking about, there is a reason it scored so low.
I don't know what world you live in but the hardcore sim racing community does not view forza 5 as a must have racer, especially since you must buy:
1. xbox 1- $400
2. Racing wheel- $100 for the worst wheel you can buy and doesn't have a clutch (why even bother) to around $400 for the other two racing wheels that do not look like they will fall apart by simply touching them.
3. Then the game for $60 + DLC packs
Is Forza worth $800+? Fuck no
Plus i don't even know why you are comparing drive club to forza, at most driveclub can be considered simcade, have you seen its gameplay? Other then you having to break on turns it looks like an arcade racer with how forgiving it is. Even forza is better then that.