The avatar can not stand still on slopes and slips slowly down. It would be better if that were not like that. In the reality you can also remain standing.
This is a common problem with inaccurate friction simulation. Not all virtual physics systems simulate static versus sliding friction properly, and given physics here is in alpha, it could be that the coefficients are not tuned. Moreover, when the avatar’s collision hull is modelled as a capsule (quite common in many virtual worlds and in HF), that spherical bottom presents an unnaturally low friction contact.
To compensate for that deficiency, the character controller logic can increase the friction coefficient significantly whenever the avatar’s velocity drops below some threshold. That stops the terrain slip. And too, the terrain entity’s friction needs to be increased.
Wait we and see, the fine tuning is still safe.