Closing the park during refurb? Seriously? 90% of it is still great, and the stuff that's being replaced will not be sorely missed. In the meantime, CMs would get dumped, and rust would build on perfectly good headlining attractions.
Plus, without the current cashflow, the refurb would likely take years longer and/or would be undoable.
Look, nobody's pointing guns at guest's heads to force them into ponying up the money to come in. Lot's of people still want to come. I just spent 10 days at WDW, and we spent parts of 3 days there on our park hoppers. We had a great time, and Star Tours, R&R, ToT, Midway Mania, Prime Time Cafe and Fantasmic made it onto our top ten lists. (All 5 of us did a top ten list after the trip, meaning 50 things were mentioned. Of the 50 things, 9 were from Studios, and the cover of our memory book is of the Star Wars fireworks over the Boardwalk.)
I wasn't around when Walt was running Disneyland, but I have never heard of him closing down the place when work was being done. Yet I'm quite sure that areas were walled off during maintenance, additions and refurbs. I would assume that Walt would have cried if guests showed up at a locked front gate ala the Griswolds at Wallyworld. NO! Walt definitely would've kept it open so guests could see it all as is, walls and all. It's insane to close it right now, especially after the tremendous buzz of interest with the new Star Wars movie.
Right now, Midway has a 95 minute wait, ToT and Star Tours I are at 20, and R&R is at 40. I also assume that thousands will be at Fantasmic, and a very healthy crowd will thrill at the John Williams accompanied fireworks tonight. These guests want to be there, and are willing to pay. Are you so much wiser than them? Do you think that you or some other Disney purist should dictate to them that they should cancel their hopes just because, "Gee, it isn't as perfect and utterly amazing as it should be"?