The problem with this mechanic isn’t just perception. Imagine being able to craft an item that you can place down and suddenly a whole grid square is now claimed and no one else can build there. It would take even less work than it does today and, let’s face it, today it takes too little work – isn’t that part of what we’ve been complaining about?
So, naturally, if we’re proposing a mechanic like that as an improvement, people will assume that the radius isn’t huge. And then you get complaints and discussions about just how big or small it should be, because everyone will have a different opinion and everyone will be convinced that their opinion is the right one. If you try to provide a “one size fits all” solution, the only thing you can be sure of is that it won’t fit anyone
That’s why I believe that a new claim mechanic has to come hand in hand with some kind of upkeep mechanic. Sure, everyone will still grumble and complain, but they’ll have more freedom to experiment and you avoid both major pitfalls: 1) everyone feels too constrained, 2) trolls can place huge claims with even less effort than now.