If you don't have data caps, be happy. But, they're still very common and even if you don't have them in your contract, you may get penalties applied after some threshold.

The cost can be also in concurrent access. Unless you apply a heavy QoS on your network, serving filecoin network may degrade your other tasks.

Now if you don't have caps and want to keep it that way, I wouldn't be excited about filecoin. Unless you're actually paying for guaranteed bandwidth and it's part of your contract, your ISP is overcommitting. The moment people actually start relying on that fact, the ISP can do one of: raise prices and buy more pipes, lower the speed, reintroduce caps. The first one is a limited resource that takes time to apply. The other two are quick and known solutions.