I've said it before and I'll say it again - you were never going to get a 'true' successor to the Supra from Toyota and the main reason is brand positioning.
Back in 1992/93 the Lexus aspect of Toyota was still mainly a US brand and in its relative infancy. When the Supra was released (at £37k back then!) it was the pinnacle of the Toyota/Lexus stable - you simply couldn't buy anything more powerful, faster or better, end of!
Fast forward to 2018/19 and the story is quite different. Lexus is now the premium brand in the Toyota stable and, as with Porsche and its model hierarchy, so it is now with Toyota and Lexus. Lexus have the LC500 as the brand leader and very soon the LC-F. THAT will be, technically, the new Supra and in my opinion should be considered such. Toyota cannot bring out a model that usurps the Lexus in terms of powerplant, power, speed and cost - brand positioning just won't allow it. The Toyota Supra of 2019 is effectively the Boxster of the Toyota stable whereas the LC-F is the 911 Turbo. I'm as disappointed as everybody else to be honest as when I first the the FT-1 concept I had high hopes but when the spy shots came out is was always a disguised Z4/5 under there and as with the GT86 (which is a fine handling car) was always going to be a diluted successor. Don't blame the Toyota engineers, I'm sure they would have loved to produce a true Supra, blame branding.