Besides how obviously rushed it was, I was actually pretty satisfied with this ending, though that's probably because I usually like realistic or bittersweet endings.
Some have already talked about this, but I think the message here is not really "dreams don't come true" or "submit to the capitalist machine" or anything like that. I think the message is more "life has ups and downs, and if you're in a relationship with someone, you need to work together and support each other through it all." I like how Haru and Hinoto stayed together even after this awful rough patch. I like how they're still each other's rock. And I like how the ending implies they'll try again in the future once they're more financially and professionally stable (which I headcanon that they do).
Most of all, I like how they don't blame each other for their problems or failures. Even during their own individual breakdowns, their primary concern was the other person's happiness. Haru felt like she failed Hinoto because she wouldn't be able to support their new life on the island, and Hinoto felt marriage put pressure on Haru. At the end of the day, they wanted each other to be happy, and they're happy with each other.
On that note, Haru and Hinoto seem to already be married. In sickness and in health and all that. No matter what problems they face, they'll face them together. And I think that's just beautiful.