Bards aren't that great.

They certainly aren't top theoretical dps.

However they were unimpacted by movement.

Melee was severely impacted by movement.

They are buffing melee movement (utility, not damage), and they are nerfing bards in some way.

Because it seems like restricting their movement is a stupid idea, likely it is just a small nerf in the area of 5-10%.

To give you an idea of how little this nerf will actually mean for you, a 10% nerf to 1 dps (assuming tanks do 25% of a dps's damage, and healers do 0%), you lower the raid's damage by 2.3% total.

Now this means that a 10 minute fight, it will take 13 seconds longer.

You'll live.