For clarification: I was imagining the the solver machine had the same number of resources as the problem machine (e.g. same length of tape, same number of stat

For clarification: I was imagining the the solver machine had the same number of resources as the problem machine (e.g. same length of tape, same number of states). I of course agree that there is a Turing machine that decides the computability of LBAs. When I said the problem still existed I meant you'd need e.g. larger and larger LBAs to solve the LBA problem up to a given size and that an LBA of tape size K with M states could not solve the halting problem for all LBAs of that size.