What purpose has "basic patriotism"? Isn't it just to create a "them" and "us" division? It has nothing to do with advancing democracy, human rights, or anything positive, but only to create loyalty to your own state, no matter what.
No, but if the extreme right takes it over, then it becomes a symbol for the extreme right, and your use of this symbol will be seen as support of the extreme right.
If people want to disengage the national flag from the extreme right, they'll need to use it themselves en masse. But that is difficult if you also do not want to distance yourself from other nations.
Take a sports game event. It is generally held that you should support the team from your own country, although I can't see why. In my opinion you could also support the team with the nicest players, or those who give the most memorable games. If you carry your national flag, you are not supposed to cheer when the opposing team does something really good. You are stuck with your own side.