Ryzen are not Intel. So toss out any pre-conceived notions of what temps (especially at idle) should be.
An intel at idle drops speeds and voltages on all cores, but all cores remain active, so any background tasks get spread out amongst multiple cores. Temps are only reported on the hottest of those cores at any given time period. So you'd see 32°, but all the other cores will read @ 29-31°C.
Ryzen are different. At idle they lower clocks and voltages, but all cores are put in sleep mode except 1. That single preferred core will carry the full load of all the background tasks, and every new task startup hits high load % on single core, so you'll average closer to 40-45°C idle and spike 60ish°C or maybe higher, depending on when the actual read of temps occurs. Could be right before a spike and you don't see the temp change, or right after the spike ends and still don't see it, or right at the spike and you get a 70°C hit and freak out.
But all that temp is read on a single core, it's not the active temp of All cores or the entire cpu.
Soon as you move the mouse (1/256th of a second later) all cores are fully active and background tasks are split up over multiple cores, temp goes down proportionally.