Yes. I surely confirmed that I am using Colab Pro+ with 50$. I checked htop in the bash terminal as you pointed out, still 2 cores. I checked also with lscpu command.
I suspect a possibility that allocated Colab instance would not have equal performance. Then, I tried “terminate” and “reconnect” 20 times. However, the CPU core was always 2 cores.
I wonder there might exist a blanket ban on Colab as @Neel-Gupta pointed out. Unfortunately, Colab might have classified me as an “AI artist”. If so, my question is what are the criteria and how I can unblock the ban. If someone knows, please let me know.