All of WDW is definitely doable without LL, but what time of year it is and what you really want to do can make a real difference in the experience.
Example: Magic Kingdom. For some reason, Peter Pan’s Flight has some of the longest wait times in the park. If you want to ride it without waiting 45 minutes to an hour, you’re probably going to want to pay for an LLMP. But my family probably wouldn’t care if they never rode it again, and it’s certainly not worth $20+pp to us (you need to pay for the MP for the whole park, not that one ride). Other rides we’re more interested in like Pirates, Big Thunder, HM, can also have really long wait times or can practically be walk-on. There’s more variation throughout the day and an ability to follow the path of least resistance.
That being said we 100% bought G+ on our last trip, because we had another couple and their 5y/o with us on her first trip. Bought memory maker too. There’s occasions where you just want to make sure everything is as good, fun, and pain-free as possible.
Generally I’m going to say if you’re coming back after not being to WDW for 12 years, don’t worry about LL. Do your Virtual Queues for anything you’re interested in them that has them. Otherwise just explore and find the magic of the trip organically. If there’s something you feel you must do like Flights of Passage and you can’t either Rope Drop it or wait until the end of the day when it’s shorter, pay for that. But I wouldn’t for the parks as a default.