tfjs is dead, looking at the commit history. The standard now is to convert PyTorch to onnx, then use onnxruntime (https://github.com/microsoft/onnxruntime/tree/main/js/web) to run the model on the browser using webassembly/webGL (and nodejs if you wanted to, but why?).
A lot of what you need is already written, you just need to find the right libraries and write the bindings. From my encounters with Python ML it seems like "just use Pytorch" is a bit like "simply walk into Mordor".
Adding GPU support soon is absolutely my goal in the future!
I think a PyTorch-based JavaScript library could be useful, as PyTorch has been way more dominant than TensorFlow recently.
https://github.com/tensorflow/tfjs
I'd love to see PyTorch in JS, but I think unless you get it running on the GPU it won't be able to do much.