What do you mean with inpossible? You are aware that what radio equipment does is often equivalent of analog operations like multiplication, addition, etc. just at high frequencies?
Sure accuracy is an issue, but this is not as impossible as you may think it would be. The main question will be if the benefits by going analog outweigh the issues arising from it.
In general the problem with analog is that every sequential operation introduces noise. If you're just doing a couple of multiplications to frequency shift a signal up and down that's fine. But if you've got hundreds of steps and you're also trying to pack huge numbers of parallel steps into a very small physical area.
Sure accuracy is an issue, but this is not as impossible as you may think it would be. The main question will be if the benefits by going analog outweigh the issues arising from it.