Quelle is the latest developer update from DTG as posted on their homepage. All the things that would really have made a difference performance wise has been deemed too expensive.
Look up the section about multicore support yourself. It’s the section headed Performance Improvements. Read thoroughly! You will find that everything that really would have made a difference has been given up.
Dows TSC need them. Yes, because those things would have allowed a broader userbase to run it on good settings. More userbase = longer lifespan for TSC.
Add to that developers has a need to evolve, and make money, and the limitations of TSC performance and development is a limiting factor.