USB is crap because:
* Uses polling rather than letting devices tell when service is needed
* Half-duplex with associated latency, superpositioning wave amplitude, speed and predictibility problems etc
* Use of single ended signaling for out of band signaling
* Hierarcical structure enforced, more complicated than a bus option
* Single master (OTG is patchwork)
* Limited to 127 units
* Insufficient power 2,5 W (vs 45 W for firewire) which makes 3G dongles etc out of specification
* Lacks galvanic isolation with signal transformers, like Ethernet is designed
ISA was in essence replaced by USB because they are on the same performance level and both serves as "geekports". PCI (and MCA/Zorro) are something completely different with autoconfig, wide bus, thought through transfer phases etc.