Usually trading with demo is actually good but for a quicker process or fast learning methods I wouldn't encourage someone to use their demo instead it's better to at least spare little money to trade in real account because Demo and Live accounts aren't operated the same way, there is much difference when you trade on both realistic accounts and Non-realistic account, you gain more life experience compared to when you are trading on demo and of course you wouldn't be that focused on demo compared to how you be careful while trading with real money, I am talking out of experience.
I think it only has to do with our thinking. Demo trading can be real-time too but maybe we are only too confident or can care less because we know that we won't lose anything here. If only we will treat demo trading the same as the real thing, then maybe there won't be any differences at all? Real trading must have a minimum amount for trades and I think these amounts are not that low.
So if we are only poor, we can't still practice or practice that often. This is why we might still be needing demo trading. We are often told here to not rush because many believes that it will only lead to disaster. So don't worry now, if you think demo trading delay things.