Why does Scotland's "democratic right" take precidence over the rest of the union, a union it voluntarily joined and democratically rejected leaving in 2016?
You sound like you want everything your own way. It's a fair compromise and helpful for people of Scotland to make an informed decision. The UK concludes an FTA with the EU. Then that FTA can be scrutinised by politicians/campaigners and have them judge whether being in an independent UK with an FTA with the EU is a better option than leaving the UK Union and rejoining the EU. Voters in Scotland can then look at both scenarios and see which one they prefer.
It's to ensure the correct decision is made, not one made rashly because of the attitude of "fook the Tories"