Stop me if you've heard this before, but I now have had the rear Bridgestone step out on me 3 times, catching me by surprise each time, on the GSA.
No hooliganisms, just sporty riding on clean dry pavement making a 90-degree turn each time. The tires have only about 4k on them, or a bit less, and they do not have my confidence any longer. Standard pressures, 40psi in the back and each time the tires were not cold.
Having said that, these are the stock 90/10 (street/dirt) tires on a 2022 BMW GSA, and not the BT 32 / 36 / 38s y'all run on the ST. My 1300 has the BT38 out front, CT in back and I've not slipped yet.
And I ride the ST just as sporty as the GSA, when the trailer is not there and the roads are dry.