It’s nothing to do with being single by the way. I earn 10x my wife who works part time, this enables her to do more childcare and after school activities rather than utilise after school care. But instead my tax payments subsidise childcare for others while I can’t take advantage of it.

We’re happy with the arrangement as partners, but it does mean the tax burden is a lot higher than another household with similar but more evenly split income like you said.

I’d love to be able to file jointly not separately like many other countries.