The neat thing is, Income Splitting mainly encourages picking up a trophy husband/wife for people who earn 200k$+.
You get really good ROI on that. Just make sure to sign a good prenup.
It has smaller benefits for other people with less difference in income. It generates a significant disincentive for a non-working spouse to start working part-time and getting back into the workforce.
Yes, it is money for everyone. The interesting part to me is, who benefits the most.