I would understand that argument if the underlying data-fetching implementation was likely to change. But I’m pretty confident that http-requests are unlikely to change in a significant way any time soon. And even if, is it really a big difference if you change one line of code in the Effects vs changing one line of code in the service?

For components I fully agree. Only the top-level should be connected to store and pass data down as props/inputs to child components. With some exceptions as usual :)