"Yes, FJ is hedging with ARM but they're still advancing SPARC too but they'll need a supported OS."
FJ plan was to introduce a new S64 cpu in 2021. that plan was cancelled, and most probably they will present just a speed bump on the current S64 in the same timeframe, with no major hw change. basically what we have done with M7->M8.
reason is that we don't have resources to code a new Solaris to support all the new hw features the new S64 included. we don't have resources in Solaris R&D basically to do ANY enhancement, only support critical level SR (sometimes, not always) and include some open source sw pretending it's a new feature. this is true since long time, but with the latest layoffs it's really to a ridicolous level.