Hi and welcome, Jase. I agree, probably they are Yucca. They're very low-maintenance plants that like very little water and really don't need any care to speak of. The flower stalks are beautiful, quite tall with nice cream colored flowers. That bed with the white rock mulch is a great place for them, and to be honest not much else will grow in that stuff.
They do have very sharp, stiff pointy leaves though. If they're anywhere near a walkway or driveway where they're going to poke you, (or especially if you have small kids!! ) just take your scissors out there and cut off the very tips of the leaves that are pointing at where you walk. Maybe the last 1/4in. of the leaf. You won't even notice them missing except no more jabs.