This is not maybe, that is how it works. The more popular Ethereum blockchain is, the more transactions people want to do, the bigger price for a transaction miner set. This is all about demand. And it is obvious that the more Ethereum cost, the more expensive transaction is.

Right now it is safe to make a transaction with 55-60 gwei. This morning users could pay <30 gwei for slow transaction. Slow does not mean you need to wait hours before transaction is confirmed. Sometimes slow is few minutes slower than a normal transaction.