Because not everybody can:
A. Afford a high-tier PC capable of running Virtual Reality AND Java Minecraft; Most VR Rigs cost almost $500 without the added computer, which can easily run up to $1000 with just the minimum VR specs;
B. Not a lot of people want to do the overly-complex task of modding an Oculus Quest to run the SamsungVR version of Minecraft, just to keep needing a Xbox controller(or other bluetooth input).
And the game does not look awful, at all. That character model, absolutely doesn't look nice, but the average appearance of the game is better than most of the same genre(of minecraft clones; take Voxel Works Quest, for example).