Yes, it makes sense to backtest the last few weeks, and if you see the EAs doing well, you can keep testing/trading.
What you said is correct. I see many traders rushing into live. Many never step on a Demo at all.
This comes from the many scam brokers, websites, and services that promise profits with a single EA. And many start to believe that one EA will make them millionaires.
Even if someone hits many times into a scam and loses money, they start to think, ” Alright, this was a bad choice, but I will find the one EA that is profitable all the time.”
We all know that with one EA, we can not accomplish a lot, and it takes so much time to test and find yourself comfortable with the profits you are making by trading many EAs, only many markets, on many different timeframes.