You would have to replace the router to use wifi6 to use wifi 6. This is very new technology so it is expensive yet. There is very little information out as to how much actual improvement people get in their house. We know the wifi industry must still be telling the same lies they do with the current technology so it will be a tiny fraction of what they are saying.
If you have ethernet it will always be more stable and faster than any wifi. Note if you use the fake number rating they do for wifi your 1gb cable actually has 2gb by adding send and receive speed together. Ethernet though can actually do that unlike even wifi6, it is still half duplex even after all these revisions.