1. The speed of designing and working with patches is infinitely faster than midi (or mouse and keyboard).
2. You can achieve sounds in hardware that are not achievable in software (despite what plugin companies tell you).
3. Expression! The Keybed on most synths are far, far superior to even the most premium midi keyboards.
4. Saves tons of resources on your studio CPU, allowing you to work faster and stack sounds faster and more efficiently with a greater overall sound quality.
5. The RAW sound (no effects or gimmicks) just has a different weight that software just hasn't got right yet.
Hardware Synths are musical instruments, and musical instruments by design are the best way to create musical ideas. I want my studio computer to help capture and shape my ideas, not be the only instrument in my studio. THAT would be a sad studio to create in for me.
Worth noting that I look at it from a professional musicians standpoint. Hobbyist may not share the same fondness for the creative process which I understand. Different worlds!
