I don't know if a complete reformatting of the phone and a complete reinstallation of the latest version of N5 compatible android and the latest UT version will have a positive effect but why not.
But as I don't want to render unusable my tel which still works correctly out of this overheating problem especially when surfing the internet (not in Hotspot mode). I would need a very precise step-by-step tutorial with the commands used, which will probably be useful for many.
If someone has already successfully completed the procedure and who can write a precise tutorial, that would be great. The starting point is a Nexus 5 under UT.
I will do this with Ubuntu 16.04.
I will wait for the OTA 10 to be published and do probably this during my next holidays...