With the FR-S they were trying to pay homage to the 2000gt. Simple, clean, and elegant. They did that and now it is time to move on.
The FT-1 is on a lot of people's radar after its debut. People still talk about it and want to see it as a Supra successor. When your design studio does something right, you don't ignore it. Adapting a more FT-1-centric design makes sense. While using the current gen FR-S as an interim solution isn't great, the car was due for a refresh and switching brands in the US is a great way to introduce a different design direction.
I agree the 86 is busy and nobody will remember it as the good design, but you do too little and people accuse you of being lazy. Too much is too expensive. So they schlepped together a new design that gets people talking. The future of 86 from a design standpoint looks very good. Just not with this refresh. Until we get Gen 2, well, be happy it even exists because neither Toyota or Subaru really, truly need the car to survive.