I would not compare leverage trading with gambling. In my opinion, gambling is more tied to luck and chance, while trading is a more rational, calculated activity. Leverage increases risks, no doubt, but the essence of trading remains the same. If a person trades carefully and prudently, then he will do this, with or without leverage.
Gambling and leverage has some similarities to some extent. Whatever decision you make in gambling, the outcome is not on what you expect it to happen, the entire outcome depend on what happen in the field(for sport bets) and if you do the comparism with leverage trading, when you place your position either long or short, you don't have the final say on what will happen later, it's the market move that will decide. So playing this kind of risky games means you are hoping it happen in your favour which is pure gambling.
Spot trading is different from leverage trading, the risk control in spot trading is far less than leverage trading depending on your leverage size, the money you are dying hard to make, if you are patient enough you can make it spot trading. It's all about been patient and buying at the right time. If anyone has bought some chunk of Bitcoin at $20k with good amount, I see no reason why someone will be fighting to long/short market at every opportunity.