I’m 50+ and my resting HR is 46. As i’m sat here now it says 53, a few minutes ago it said 60. You can’t tell anything useful from moment to moment looking at your HR to see if it looks like a candidate for being your current Resting HR.
If i’ve been hammering the intensity a bit in previous days and my body needs a rest then my morning reading of sleeping minimum HR might be in the low 50’s. If i’m rested then it’ll say 43. I add this data point into the mix of other things like “Can i be bothered to ride hard today or shall i ride up a mountain in zone 2 on Fulgaz?” “do i fancy VO2 max today”, “am i tired?” “Have i done a reasonable mix of sessions this week yet?”.
So - for sure Yes your resting HR tells you something about your system that day, but only if you use the correct data (and interpret it correctly)