The only benefit I can think of is prevention of [accidental?] modification of `state` within your selectPropsFromState functions or within rendering code itsel

The only benefit I can think of is prevention of [accidental?] modification of `state` within your selectPropsFromState functions or within rendering code itself. Which is something you should never, ever do anyway, and the mistake should be quite obvious given redux's suggested structure. Given ImmutableJS also has a performance overhead in ES5, I'd definitely agree with you.