He only cared insofar as he wanted a veto, mainly. He didn't want to get railroaded into something that wasn't his idea (though as we've seen, his best work is when he's not just doing his own thing). The "EU" isn't even necessarily consistent with itself, and Lucas would have had no issue just ignoring it completely if he didn't want to follow it.
The EU has some unmitigated shit in it, btw, just Rick-tier garbage. But it has some real gems which could have been used for good stories - except they obviously don't want to do good stories, they want to promote an agenda.