The last blocks are indeed a bit boring, but :
- you can use upgrades like "puck controls ball", "Easy Cleanup" and "Wind" to make it easier
- managing to clear everything without missing the bricks is rewarded with more upgrades and options, which let you progress much faster.
I'll consider bricks falling from the top for an "end boss" level that just gets harder and faster over time until you inevitably lose the ball.