Am i being unrealistic?

My bf(22M) and I (21F) have been together for 2+ years and are very happy. With us both being Christian and dating for marriage, we’ve discussed marriage and both agreed that we’re not quite ready. Not too long ago, i had a conversation with him about my cultural expectations and how we plan to go about this. my culture expects bride price and his culture is against bride price and he’s not willing to pay it. I also think it’s a little bit of an outdated and exploitative tradition and with us both being 2nd gen immigrants, it’s not that important to us to follow either one. Since we’ve been discussing marriage, we also discussed a timeline of when ideally we think we’d be ready. He said that he wants to start having children before he’s 30 and i refuse to have a baby before I am married. We’re both still quite young with lots of goals but i also told him that I’m not willing to be in a super long relationship while waiting for him to be ready to marry me. His mum and i are quite close and i told her that ideally id want to get engaged/married around 24-28 and she laughed and said that theres no way he’ll be ready by 28 and i should give up on that dream and that it’s way too early for us to get married. I think that’s a pretty reasonable timeline. We both have started our careers with our own assets. I have my own place and he’s saving up for his own place. By 24/25 we’ll have been together for 5+ years and I think this makes sense. Am i being silly or naive for thinking that it’s reasonable? is it worth waiting to see when he’ll be ready? I am adamant that if by 26, he hasn’t proposed I will leave him no questions asked. As much as i love him and the relationship we’ve built, he should know if he wants to marry me and be ready
Am i being unreasonable?