I can only offer my experience as someone who runs five different Unifi sites from a cloud controller. One site is commercial with a USG Pro, and the other four are residential with 3-port USG.

I notice that the NanoHD and AC Mesh APs run warm to the touch. AP-AC-LR and original AP (green light, no 5GHz) run cool. I also have an AP-AC-Pro deployed at one site, but it's up on a loft I can't reach. None of the APs I have on my controller report temperature.

The USG-Pro is reporting CPU temp of 88ºC and board temp of 56ºC. The front panel is ever so slightly warm to the touch, but I modified the USG-Pro with quieter fans. This is the only site I have IDS/IPS enabled on.

I've had many different hardware revisions of 3-port USG over the years. It's my opinion that the newest ones feel noticeably lighter than the older ones and operate slightly cooler. This could be due changing what the case is made out of. I have an older one at my house and it doesn't feel very warm to me. Certainly nothing that would alarm me.

In an office down the hall, we have an 8 port 60W switch like you have. There is a PoE load on two ports. One is 4.74w and the other 6.90w. I would say this is the most warm item. My controller has a field for reporting temperature, but it says "No Sensor." I am not sure if there is a version of this switch with a sensor. The switch is definitely warm but again I would not be alarmed by it. It's a fanless managed PoE switch with a load on it. The case is metal and the heat seems appropriate.

In my house, I have the PoE passthru version of the 8-port Unifi switch with no PoE load on it. The case is basically the same as the 60w PoE version but missing (most of) the PoE status LEDs. This switch is not warm.

At another site I have a 150W 8-port PoE switch with only one 3.74w PoE load on it. This switch is much larger than the 60w and might contain a fan. The controller is reporting a temperature of 56ºC. This switch never feels warm.

I have a 16-port PoE 150w switch out in the warehouse meant to run PoE cameras that are not hooked up. So, no PoE load at this time. Controller says 61ºC and the case is just above body temperature. Barely noticeable warmth.

I also have a non-PoE 24 port in a rack. 69ºC according to the controller. Not at all warm to the touch on the face.

One thing I should mention is that one of these sites didn't have the space for a 16-port Unifi PoE swich so I ended up installing a Linksys 16-port (8 port PoE) fanless non-managed switch there. I believe 3 or 4 of the ports have a PoE load on them. This switch is not warm to the touch despite being fanless. So, it's possible the CPU in the Unifi 8-port 60W is simply inefficient. But, I've had managed switches in the past with fans that sound like a jet taking off.