These are people, stop making it sound like you can just ship them anywhere - they are not animals!
Russia is huge though, it could hold them - but you see immigrants wouldn’t want to go to Russia due to the fact it is somewhat corrupt.
The UK is fulfilling it’s role, this is the US’s issue. Agreements with the EU are not really irrelevant either, we allow members of the EU in, to take advantage of our workload and education, being a part of a community requires us to do this, and an unfortunate consequence of this is cutting back on immigration - because we have so little space.