But wtf, it's like life is everywhere. In black or white, it seems that every relevant creature has lifelink AND even aditional abilities or good stats. In general creatures are pushed so hard, it seems pretty futile to not use a creature heavy deck.
Yeah, things changed A LOT. At first creatures started shaping entire formats: when Thragtusk came out, you either played Thragtusk or you died IRL.
If you compare this to what was considered a strong creature in the past (i.e.: the Serra Angel), it's clear that creatures have come a long way. At first a "good" creature was a creature with an acceptable body, but then the design teams had a sudden enlightenment: to be better than the removal that kills them, creatures have to do something even if said removal gets played. To do that, a creature has to (1) do something when it enters the battlefield, (2) do something when it leaves the battlefield, (3) be VERY hard to remove, so that a simple removal isn't enough to deal with it, or (4) have a TRULY exceptional body, so that if the removal doesn't get played on time it can have a real impact on the game. Basically, to compete with instants and sorceries, creatures have to become instants and sorceries. Another great example obviously is the Siege Rhino:
The "Tarkir block" had tons of great beautiful creatures, but none of them can even hope to compete with this monster. To get a feel of what was like to play when this guy was standard-legal, you should watch the first 25-minutes of this video: