No I think the point he was trying to make was that it could be dangerous if his sub is completely dependent on him. He wants him to retain some sense of freedom in case anything ever goes wrong.
A healthy relationship is one where you can say 'no' without fearing the consequences. If you're completely dependent on your partner, both in the bedroom ánd financially it will become more and more difficult to refuse stuff and say no. He wants his sub to be submissive because of his own free will, not because he feels obligated to do it. I think in a way, this is also caring for your partner.
every relationship is different, but for theirs i think they like a clear cut boundary within and outside the bedroom. with this kind of dynamic, its /very/ important for the sub to be independent, and for the dom to not have too much influence and control over their everyday life. otherwise, the boundary can be a bit muddy and in worst case, the relationship might even turn toxic. but ofc, like i said every relationship is different. its not always like that, but this sort of way of navigating things is quite common.
How does financially helping your boyfriend who quit his job for you is unacceptable? it's not like he'll dependent on him forever...Shouldn't a dom help his sub and be there for him to take care of him no matter what? even in the real world outside of the bedroom? or does the dynamic stop at just the bedroom?