I for one thought "It can't be that hard to get a YGT or the equivalent machined independently". Well we have seen that it can be fraught with difficulty and unforeseen setbacks. The problems kinda make me regret that I didn't get one of those stainless steel platters off Yahoo Japan Auctions when they were available(150000 yen at the time).
Subsequently, members stuck their neck out, to canvas machinists regarding the possibility of having an exact YGT custom made. Brave stuff and inspiring as well as some disappointing results. With the supply and demand situation inflating the price of YGTs. The obvious incentive is to save thousands of dollars by bypassing the supply bottleneck. Get one machined.
We have already had testimony(I can't recall who...) from a user with a stock platter that the sound quality is decidedly better upon substituting the YGT( ie more of the good things that the GT 2000 series brings to the table). It isn't necessary but it doesn't hurt the sound quality in the least. If one doesn't want it. There is ZERO pressure. Pimp your GT 2000 or don't pimp it. It'll sound wonderful with nothing more on it than records and a cartridge.
However for those who love that sound and want more of the same: The GT 2000 is the pimp turntable to end all pimps. It was envisaged as a 'all the bells and whistles' project at the blueprint stage. I'll refer back to Tekniknissen's find of the prototype GT-7, which had the socket for the external power supply. The turntable was designed to incorporate the other elements. So who would decry anyone wishing to taste that?