Maybe if you want to buy big amount of bitcoins or Ethereum then it is the right time to do so because currently the market is already all red and easy profit if the trend reverses and the market goes up. But if you wait for the market to go down further then it can be a bad decision as no one has ever predicted the bottom correctly so you are also not a special person, I would suggest you to not wait for bottom and buy whenever you can get a great position to buy like today itself.