IMHO, this has been blown out of proportion. The attack exists, but it is fairly expensive and difficult to pull off. There are some simple things implementations do now like actively rebroadcasting the HTLC_timeout transaction, watching the mempool, and limiting their exposure by restricting the amount and count of HTLCs in flight which make it even harder and more expensive. If you have a lot of money on a Lightning Node, be sure to be on a recent release and check your configuration, but other than that, it’s just one other way how you should be attentive of a hot wallet deployment and manage the amount of risk you’re willing to take.