Does high leverage 1:1000 mean high risk? Should I avoid 1:1000 leverage no matter what?

Please note that the maximum leverage setting allows your account to open a position bigger than your deposit. At the highest setting you can still open the lowest lot size available.

The risk comes from choosing how much volume you want to trade and your allowable stop loss level.

It is the clients responsibility to plan out their leverage and trading volume based on their risk management.