We can chose to ignore twitter, and I'm sure many of our generation do, but millions are influenced by it. As of 2018 there were more than 320 million who accessed twitter at least once a month and are doubtless influenced by those they follow. That is why politicians like Trump tweet all the time.
Arron Banks is a dangerous individual, his poisonous ultra right wing ideas, almost certainly funded by Russia, were promoted by the brexit liars and climate change denial is a key policy of the ultra right, hence his attack on Greta Thunberg.