Stop in for a cup of coffee

Okay, opinions needed. This evening in the drive home, the Jeep suddenly got soft on the right rear. Skiddish like. I’ve checked the suspension, tire/rim, sway bars etc. everything feels and looks good, no excessive play anywhere. Is it possible for a tire to go soft? It is worn about 60 percent. Tire pressure is at 50, max is 55. All 4 tires are at or within a lb or two of 50.
Hit a curb and brake a belt?