I don't get it... so Bitcoin lets anybody put any data they want into the blockchain, and we have to haul that data around forever?
Is this accurate? Are there any plans to mitigate this issue?
There is not a problem with this. Firstly, legitimate transactions are indistinguishable from arbitrary data. Secondly, to avoid pruning and to send the transactions in the first place, there is a cost. There are no plans to mitigate this issue because little data can be stored for a high cost, and the fact that this really isn't an issue in the first place.