I used TF back when deep learning taking off, around 2016. Personally, it began really hard to use when TF allow contribution modules to merge into codebase, inconsistent API interface and wall of deprecated warning appeared everytime I run code or update TF version. I think most of people back then use TF or Pytorch to try out research idea and TF just didn't work well for that role like Pytorch. More and more reseaechers switch to Pytorch for easy use and so are their new models, I have a doubt that there is still anyone published model on TF beside Google.