Can a decentralized currency like bitcoin ever get regulated?
No. Bitcoin is decentralized and censorship resistant. Only exchanges and centralized services will be regulated and this is not new.
I think it depends on the context of regulation. As far as the blockchain itself goes, that's a straight flat NO. Can't reverse something that was purposely created to escape the same sick centralisation cycle.
On the other hand, any monetary value derived from possessing Bitcoin or using the system can be levied in one way or another.