How to look past the fact that I probably have chosen the wrong research area?
Don't think of yourself as stuck in a research area. You are starting to gain some independence and can also start to morph your research into any area you choose. Over your career you might do this multiple times, actually.
Use the post doc to start to explore the areas you'd rather work in as much as you can.
Staying with your doctoral advisor might not be your best move, though with coronavirus it may be necessary in the short term as you note.
Your PI for the post doc might be able to give you some freedom here. But even if not, increasing your reputation in one area can lead to more freedom to move and change your direction.
Your career needn't be an arrow.