To Be Fair
Move towards tub assemblies rather than separate tubs prolly has much to do with washing machines becoming more likely not to be repaired either outof design and or cost or both.
Aside from SQ, Miele and perhaps a few others, it is rare to find long warranties on tubs, bearings, motor and such as of old. If the washing machine will last on average only four or five years (sad, isn't it?), before requiring a repair that may cost more than replacement, then what is the point of having tubs that will last the duration and or designing for bearing replacement?
On any front loading washing machine, replacing the bearings is not usually an easy job, nor very cheap. On Miele units one has to have not only the knowledge,skills, and tools, but a winch as well to lift out what amounts to roughly more than 200lbs.
Commercial front loaders such as those found in laundromats OTHO are designed for bearing replacment, mainly because of their long life and abuse taken.