test and trace is so swamped at the moment that although they may ask for details somewhere it's not being followed up by anyone so as long as you don't have the pinger on you won't be contacted.
Yes, this seems to be the case. Apparently they aren't even contacting all positive people in person, but sending texts instead, telling them to read about isolation on the internet. 
I got a text giving me a (broken) link to "add my contacts if asked" which seems very wooly, as I haven't been asked because I haven't been called. They seem most interested in "high risk settings" which they say are health settings, care homes, places like prisons, food processing, and "pubs that don't serve food" (but only if you're staff!) Oh, and international travel and airports. If you report you've been anywhere else, it is "allowed" to be other hospitality/ accommodation/ education setting/ workplace/ parties etc - but not shops, gyms, leisure places like cinemas, museums or so on, or other travel hubs, which all seems a bit odd. Needless to say I haven't filled in anything (as I haven't been asked to) but will do what I can if I am asked.
They also gave me a code to put into protect scotland, so it will ping anyone within 2m of my phone (but not necessarily within 2m of me! Doesn't seem to acknowledge that women don't tend to keep their phone physically on them all the time as WE DON'T HAVE SENSIBLE POCKETS) who has that kind of thing enabled.
Not entirely convinced this is test and protect being it's most efficient, to be honest!