Although it is a shame that the boat has been cut up, and it does mean you can no longer walk from stem to stern inside her, I think you have to understand what a very poor state U-534 was in. I was fortunate enough to go on a tour of U-534 a few years ago when it was with the Birkenhead Historic Warships Collection, and very cool it was too, but it was apparent from the tour that structurally, this was a state of affairs which could not continue indefinitely, and it would have been massively expensive to try and restore the thing in one piece.
Although on photographs you may have seen, U-534 looked reasonably sound, the truth is that the conning tower was almost completely gone and much of what you see was a replacement fabication, the guns had disintegrated and the decking was almost all gone, revealing the machinery and workings normally covered by the deck plates, something which was only apparent when stood on what was left of her decks. To enter, you had to go through a torpedo loading hatch and although she was in pretty good shape inside, with lots to see, the interior had spent many years - before she was raised - flooded up to about halfway, thus, much of the flooring was gone and the superstructure below deck level was corroding away to dust, and this was all supported by a hull which was also on its way out, so keeping her in one piece without literally millions of pounds worth of remedial work was simply not an option, and probably the only way to stop the rot was to cut her open in order to stem the decay.
Chock