i would be shocked if its not seriously stopping others of u from depositing on coinroyale who arent huge whales.
Unfortunately, all of the crypto casinos and neither all of us here on bitcointalk will be able to fix/reduce an issue with the bitcoin transaction fees.
Also the amount (BTC/USD) is not a caused of the issue, but the inputs on that transaction. Multiple inputs = bigger transaction size = bigger the fees.
Transaction fees spike in times of extreme network congestion, and there is nothing we can do about it except:
You must use a wallet where you can set the transaction fees by yourself e.g Electrum wallet.
Here is the website to check the average bitcoin fees (live) https://mempool.space/
All I can suggest now is, buy bitcoin on any app/wallet where you can control the privkeys, and import the privkeys to electrum wallet.