Simpler in terms of absence of unnecessary cabling, I/O and PSU interference: definitely. Also, high efficiency speakers with low powered tube amps can do wonderful things
Complexity however is a must in the current development stage of digital: cleaning up the Ethernet signal through cascading reclocking switches as well as reclocking the USB connection tend to yield sizeable results as does reclocking DACs where design allows it.
Equally, cleaning up the power supplies via filters, transformers and conditioners as well as fuses, connectors and cables is 101 for good sound.
Finally: given modern dacs, many systems don‘t benefit from a separate pre, so simple direct to amp can be better.