No question, some coach makers do a TERRIBLE job of providing access to mechanical systems.
But, unless the buyer puts such access higher on their "must have" list, builders will not put it higher on their list either.
On edit: That brace between the forward and rear access area is exactly where you need to be to be able to clean the front of the CAC! Don't know how structural it is and if an option may be to cut it out at each side and use 1/4" steel plates on either end to reattach it. That would easily carry the weight of the floor and a person, but would not be a good option of there are other structural functions of that "mid-panel".