While this at first seems counter-intuitive, the way that counters work, if you animate a man-land that has had counters placed on it already, it will gain the effects of those counters. This means that if you cast Ruinous Path and made Lumbering Falls into a 4/4 Elemental land, you could later activate its animate cost to become a 3/3 Hexproof creature and get a 7/7 Hexproof Elemental creature for a turn.That’s certainly not nothing.
The best examples of using +1/+1 counters on man-lands are Inkmoth Nexus and Raging Ravine. The Nexus often becomes a creature in Modern Affinity and gains a +1/+1 from the tap ability of Steel Overseer. Even after the Nexus reverts back to a land, nothing makes the counters go away, so they remain there until the next time the Nexus is activated. (Blinkmoth Nexus works the same way, but it isn't as exciting without Infect.) Raging Ravine, the red/green man-land from Worldwake, actually puts a +1/+1 counter on itself whenever it declares an attack. It’s good enough to still see Modern play, as it’s a threat that keeps getting bigger and bigger.
While it may be Magical Christmas Land to hope for Awaken cards being playable in Modern Affinity to get 5/5 Inkmoth Nexii with Infect, it’s certainly possible for the new man-lands to get considerable boosts from the Awaken mechanic. Ruinous Path is probably the most playable we’ve seen, though. Then again, using a card like Dromoka’s Command to give one of your animated lands a +1/+1 counter or using some Bolster shenanigans to pump up your lands is possible. We’ve seen the power that man-lands have, especially in Modern, so while the Blue/Green one may not be the most powerful of the cycle, it’s going to show up in Standard.