Whilst they 2x or 3x scale (whatever the choice of leverage) the daily price move, over time they tend to realign to similar overall reward as 1x (non leveraged), but with much higher volatility along the way.
Note that 15% XIV and 85% gold is a proxy for 50/50 stock/gold (XIV acts similar to a 5x long stock, stock/gold 50/50 acts like a volatile bond). The above used quarterly rebalancing