For those that don't yet know, "Prelyria" is what we call our low-fidelity pre-alpha client. It deliberately uses a lower-poly art style to allow us to quickly and easily iterate on the things under development without having to devote the content team's time to highly-detailed work they're very likely to have to modify or redo every time a designer or an engineer makes a change to the mechanics in the pre-alpha phase of development.
By keeping the cost of iteration low, we can iterate more readily and that means we can do more with the resources we have. As part of the process of moving into later stages of testing, those lower-fidelity assets will be replaced with the full-fidelity artwork you have seen in other things we've shared.
(Which basically means, "We didn't decide to go low-poly on you, don't worry!")
Hope that helps! :)