Demo is virtual-money practice; real uses actual funds. Execution conditions, slippage and psychology differ, so an EA's true ability shows in real results.
A demo account lets you practice risk-free with virtual funds; a real account trades actual money. Even with the same EA and settings, results can differ.
An EA's true ability is judged most reliably by live-account results among forward tests. Whether each TrackRecord EA is real-money depends on the connected account type (about the data).