https://translate.google.com/translate?sl=fr&tl=en&u=https%3...
https://translate.google.com/translate?sl=fr&tl=en&u=https%3...
Even privacy advocates have argued that apps can, if developed well, be useful if developed with privacy in mind. See the link by the CCC or this post by Linus Neumann, who is affiliated with the CCC (only in German, unfortunately): https://linus-neumann.de/2020/03/corona-apps-sinn-und-unsinn...
Sorry if I have missed it, but to me your arguments were privacy issues and the technical difficulties (different platforms, Support) to get an app on enough smartphones to reach the critical number of participants. Don't get me wrong I totally agree, these are things that we first need to find a solution. But your post sounded to me like you have the opinion that contact tracing doesn't work.
Fear makes more people react emotionally.