Considering everything that has been said about the Wales family's move: could this move be linked to their safety and possible (and unknown to the general public!) threats they have suffered in the last years?
It's always possible, but I don't think so. Namely because Adelaide Cottage is located within the home park, which is - simply put, in layman's terms - the estate of Windsor Castle. The security operation of Adelaide Cottage is part of, or enfolded within, Windsor Castle's security operation, which means the Waleses are pretty secure there. Forest Lodge, on the other hand, is part of the Great Park, which is outside the apparatus of Windsor Castle's security operations. Meaning the Waleses have a separate and additional security operation for Forest Lodge, and one that affects their neighbors and nearby public/community spaces.
So if there were serious safety and security threats/concerns to the Waleses like what you may be envisioning, I'd think they'd move closer to security - aka into Windsor Castle - not farther.
To me, this move feels more like William and Kate setting up a long term plan should William take the crown sooner rather than later. Consider this: the kids go to school in Windsor, so should William have the crown soonish, he and Kate will most likely stay in Windsor to be close to them. They'd probably move their offices to Windsor Castle without hesitation - since Windsor hosted The Queen during the COVID years, they've probably got rooms and offices already equipped to do just that, not to mention William and Kate have been using Windsor Castle more and more to host meetings and audiences. The caveat to using Windsor Castle is that Windsor Castle is also publicly accessible - while the apartments are private, the public can still watch comings and goings from across the quad just like they used to watch the then-Cambridges at KP. That's harder to do at Forest Lodge, which has plenty of space for the kids (and friends and pets) to play and all the amenities the family might need (e.g. swimming pool, tennis court, extra room for a home gym or private offices) right there on the grounds.
By the way, the setup of Forest Lodge - lots of outdoor room, all the amenities, extra space within the house itself for visiting loved ones - is the same setup as their beloved Anmer Hall, where they spent COVID lockdown together and (by all accounts) seemed to thrive with that focus on close-knit family time. So it's totally possible that this move is meant to keep that family time/priority central as the kids grow up and the family's future(s) take shape while the outside world, and the crown, close in on them. I suspect they were able to do this quite well at Adelaide Cottage since it's smaller, but they probably wanted to a bit more space to stretch as the crown gets heavier.
And frankly, who would blame them for wanting that? William grew up under a hot spotlight. Kate spent her 20s under a microscope. They know very well and very firsthandedly what it will be like for their children, so why not create the safe space(s)* they know their children will need while they're young, before it becomes urgent and critical? After all, it's far easier to keep ahold of something if you've had it for a good bit than it is to try to create something.
*And I suspect this is why William and Kate spent a lot of time in Bucklebury with the Middletons - they found an escape there they couldn't find anywhere else, which is what they're trying to give the kids. I also think, with hindsight, William realized he enjoyed parts of his time at Highgrove more than he thought and there are elements of Highgrove he's keen to give his kids - for instance, how William's and Harry's friends all came to Highgrove to hang out, and how he may like for his kids' friends to come to their home to play and hang out. This is just speculation based on vibes and vibes only, nothing I've seen, read, or heard about.
