Well it depends on the case.

Imagine you want to anonymize an UTXO. If you already have LN channels with enough inbound, you could swap it in through something like Boltz for a 0.1% fee. Boltz would now the destination on LN, you could break this link by wrapping the LN invoice with lnproxy or similar.

Now that you have the fund in LN, you could swap them out again with Boltz or similar for a 0.5% fee. The payer of the invoice would be anonymous so this is nice. If the amount in and out are the same and all this process happens within the same hour, it's pretty trivial for Boltz to know what happened.

Maybe by using different providers for the swap in and the swap out, and by waiting a bit and not using the same amount, the link could be decently broken.

But this has some issues: how do you open those LN channels on the first place. And that paying 0.6% for the process hurts.

Now with low transaction fees you can manage to do a coinjoin of 10M sats for less than 5k sats. Let's say you do 5 rounds. That's 0.25%. And the nice part is that you could do some of those rounds as a maker, getting paid for each round instead of paying yourself. And improving your privacy even further (by not being always a taker).

But it's a good point. Maybe coinjoins are meant to die, because if the network fees are high the LN “coinjoin” becomes much cheaper in comparison.