No, the card extension is okay now since Carlos Pedroza have rectify it to be compatible with Appybuilder.
Not all of Taifun’s extensions are compatible with Appybuilder.
I hope extension developers dont need to modify their extensions to make it compatible with Appybuilder. App Inventor’s community is a huge community and App Inventor’s platforms are like siblings. This is the reason why a lot of AI users are sometimes also Appybuilder, Thunkable and Makeroid users. It makes the survival rate of these platforms is high but also fierce. So, compatibility will be an edge.