XPS 15 9500 hot at idle and hotter with normal tasks and other annoying things

I have had my 9500 for a few years and it has been great the whole time but recently things have been going downhill.

I have noticed that will transfering files to my external hard drive or just surfing the web on chrome that my laptop will get very warm to the touch right were the cpu is. Task manager shows that its using 30ish % cpu, no gpu. But the temps at idle are 60-70c and under normal chrome browsing will jump to 90ish and touch 100c. The fans are contently on and it warms up immediately from start up.

In addition to this my bluetooth mouse has been disconnecting randomly and my touchpad is lagging and slow.

I have all the latest drivers on each of the affected areas and the bios is up to date too. I have run the hardware check on the dell support assistant app with nothing flagged up. I have been getting my temp readings from coretemp.

Is there something I'm missing? Thermal paste for the heatsink gone off?