If I was down to my last $1500, No I wouldn't go, but I have taken many low budget trips to WDW.
There are a few ways to keep costs down. One, is to avoid the Jan holiday weekends, if possible.
Two, is to eat low cost. An easy way to keep food costs down -potentially - is to either bring food with you, or stop at a grocery store once you arrive. At a WDW hotel, you only get a tiny dorm fridge, so you can keep much in the way of perishables, but you can bring non-perishables, like granola bars and chips. Another potential solution is to pick up some shelf stable milk - Parmalat. You can't bring liquids carry-on, but if you are driving to WDW, or plan to shop when you get there, you should be able to find shelf stable milk boxes at any decent grocery store. They sell them to pack with kids' school lunches. If you are eating out: keep to quick serve and fast food. not great for a whole week, but doable for 3 days. At Disney Springs, Blaze Pizza is very good. The food court at Art of Animation had some decent offerings. With the parks closing early, you can also easily eat a (late) dinner at an offsite place. Just eating breakfast in the room is not a big sacrifice, and helps keep costs down. Also, drink water as much as possible. You can also pack dry drink packets to bring, to flavor plain water. One lemonade packet is enough to flavor two big cups of water, IMO. (Just don't use flavor packets in a restaurant, that's tacky!)
In the before times, we also often shared meals/snacks. Probably not a good idea right now to do that with most snacks/meals, but you can still break a muffin or cookie into two parts!
Also skip park hopping.
You might also be able to save a few$ by staying the first or last night offsite. I'm not sure how much less you can get than a WDW value, but you may well find a decent place that's offsite and save you a few bucks. Just priced a random night of Pop at $155 (about $174 w/tax +parking)), but the Fairfield Inn is only $73/night ($82 w/tax, and free parking) And, at least in the before times, Fairfield stays come with breakfast food. So that's almost $100 savings right there! And the Orlando Fairfield Inns/Marriott brands are pretty decent, as are some of the other offsite options, like Right now, I'd stick with big name hotel brands.
For just a weekend, I wouldn't bother, but one way we've gotten the most out of some low budget trips is to combine WDW with a day or two in like Tampa (about 2 hours), St. Augustine(about 2 hours), Daytona (just over 1 hour), Everglades (about 3.5 hours). A day at the beach or one of the national parks is just about free. There's usually a small fee to park, but mostly they are very low cost, except if you want a hotel room on the beach. Everglades is amazing in January! If you were really trying to keep trip low costs, and you have a car... cutting down to 2 park days and 1 non-theme park day would help. It depends where you're coming from though. Sometimes we've done two non-park days, and just visit MK for 1 day to keep costs low.
Or at least all of the above was things that were decent options in the before times. now, I don't know if I'd move rooms. Might be best just to stay offsite for 3 nights to keep the budget low. One last comment, in winter, weather can be a problem. If you'll be flying or anything, big storms can cause flight cancelations. More than once, we've been stranded in FL for an extra night during a winter trip. Make sure you can potentially cover 1 extra hotel night if you'll be flying.