That one has nothing to do with Crawford far as I'm aware. It’s just plain stupid interaction of several rules. You are definetly intended to be able to just cast disintegrate on the wall.

Some rules are intended in a certain way and just handled poorly. The above case is (I personally think) one of them. Others are actually intended to work a certain way because of designing aspects (like verbal components having to be said at a normal volume) but people simply decide to ditch them anyway, because they like something else better. Both are valid, but they are different.