"The idea isn't to secure a Democratic win, but to fairly reflect the national popular vote.'

That's naïve. Only blue states have signed up, and only Democrats support the idea. There is no "idea." There is a PURPOSE. The rest is eyewash. Politics is not about fairly reflecting the national vote. Politics is about the negotiation and settlement of competing interests, some of which are regional.

States have parochial political interests - pork, really, but still, political interests. A state that can't vote its interests because it is bound by a compact is disenfranchised to that extent. That's not the same thing as saying that those whose candidate loses are disenfranchised.