@ptillisch thanks a lot for this interesting input. I went thru almost every post on this long list and got these final conclusions:
1.) TFT_eSPI works on board platforms prior to version 2.0.15 , my working version is 2.0.9 and my not working version is 3.1.2: -> item confirmed.
2.) The issue appears basicly on esp32-C3/S3 boards, for my case ESP32-C3 boards: -> issue confirmed.
3.) Experts on HW C and C++ high level programming keep deeply investigating the real origin of this issue. For my sense I appreciate the great effort of these experts but me as an ignorant user I actually don't care a lot as long as I find any version of the platform which make my electronic components working well together. Now somebody can tell me to prefer using latest versions of SW on userlevel projects but I for myself am happy to see nice graphic, colors and fonts on my TFT display by just using what real experts provide for free on the internet and finally don't care about release numbers. I am endless greatful for this fanatic effort of highly experienced people to publish the OS of hightech HW for free on the web and I am also deeply greatful for the help I can find on this and other forums where people on lowest to highest knowledge level come together to discuss very personalized issues.
So let me say many thousand thanks to everybody who shares this place in an active or passive way. I think making Arduino better is not the purpose but using Arduino better yes it is. 
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