It sure doesn't sound like a B58 and may very well be the S58 (G80 2021+ M3)
In this video you will see a 2020 Toyota Supra Mk5 testing hard on the Nurburgring Nordschleife. Does it still sound like the B58 engine to you? Or is the S58 engine (G80 M3) being tested in the Supra? This would mean a twin turbo inline 6 back in the Supra which would be very similar to the original 2JZ... Let me know your thoughts in the comments below!