BTCUSD - Multi-Cycle Main Trendlines

Bottom is top and top is bottom?

Observations from the BTCUSD monthly chart

+ Decreasing angles of long term upward trendlines shows diminishing returns.
+ Price crossing down through current cycle's upward trendline indicates current cycle is ending.
+ Previous cycle's upward trendline becomes next cycle's top.

What have I missed? Comments down below. Thanks.