One of the benefit of UBI—indeed, for some people, one of the explicit purposes of UBI—is that it drastically reduces the need to fear that moving will be too expensive for you.
It is, of course, possible to implement a UBI that is too low to make it practical to move, but I would argue that in that case, it is missing the "Basic" part, because it does not provide enough to meet real people's Basic needs.
I think the concern many people have (and rightfully so) is that the economy is not a static system. Any artificial offsets (UBI) will just get priced into every agent's value calculation.
The thing that gives "Capital" power is that you have it, no one else does, and you're trying to transform it into some arrangement that over time creates more value than it consumes.
The transformation applied can absolutely be done incorrectly, making subsequent capital value transformations more difficult to accomplish profitably given greater constraints on the means the capital allocator can bring to bear.
Nothing about UBI substantially changes the nature of that system, therefore, the real problem to be solved, (the asymmetry of means between capital allocators) given a system that optimizes toward capital control centralization (more capital fewer hands) without also being paired with wealth ceilings via tax extraction at the top and reinjection at the bottom.
> is that it drastically reduces the need to fear that moving will be too expensive for you
Sure, that would definitely be one area where UBI would assist with but as I mentioned in another comment - it would kind of defeat the purpose of the UBI if people had to spend it on mitigating the consequences of people taking advantage of them receiving UBI
It is, of course, possible to implement a UBI that is too low to make it practical to move, but I would argue that in that case, it is missing the "Basic" part, because it does not provide enough to meet real people's Basic needs.