Having annoying activists is unavoidable, especially as long as we also have climate change deniers or climate emergency underestimaters, and therefore, we should learn to not be deterred to still do the right thing.
People opinions on what actions are probably similar to Gaussian curves, with two consequences:
1) you may be situated on the mean value, but you may not, and you have almost no way to know (personal assessments are so biased they are worth nothing)
2) it is unrealistic to expect that no one will exist on the left or on the right of you. There will always be annoying people that will go too far. As long as those are agreeing on the climate emergency problem, considering that they are a problem that need to be solved is just a waste of time. Just live with it.
If it makes you feel better, you may even consider that the existence of those annoying activists is the consequence of the lack of action of people who are downplaying the climate change emergency. If the second ones don't exist, the first ones would not exist too.