Nigel Farage is an amoral grifter. That doesn't stop him being the most influential political figure of the past 20 years, even though he has never been elected to Parliament through our democratic system.
The answer therefore is not to ignore him but to study and ask HOW and WHY he has been able to have such influence. Is it a failure of the parliamentary system or a failure of our elected politicians?
We need to understand now otherwise the UK will become increasingly prey to unelected demagogues like hi, to our cultural and economic detriment (eg look at Brexit).
Historians will certainly study him closely and how he managed to have such influence and if we want to save moderate liberal democracy then we should too.
Ignoring him is more comfortable and less scary but also avoids the problem imho.