I don't think he beat Ragnir, he passed Ragnir's test. Ragnir saw Loki was fit to wield him.
If Loki wasn't fit to wield him he would use all of his abilities to stop him and not just give up so soon. We didn't see it try to even freeze Loki. After trading blows with Loki he deemed Loki worthy, that's all. I doubt he would deem most top tiers if any worthy so it's still good for Loki.