pull down to refresh

Thanks for this detailed write up.
I'm having a hard time understanding how Robosats can be cheaper than Boltz, for swapping from Lightning to BTC.
Boltz charges .5% of your lightning total, to swap from Lightning to BTC (and then the transaction fees are on top of that).
The cheapest that I see on Robosats to "swap out" (i.e. go from Lightning to BTC) is -1.9%. So if I'm understanding right, you're getting 98.1% of your lightning btc out, into on-chain bitcoin.
Or is it somehow the opposite, you're paying LESS for the bitcoin that you get, when you go from lightning, to on-chain?