When Reform (a) put out a manifesto with some degree of economic credibility, and (b) explain how they will boost birthrates so that we are not reliant on immigration to prop up our society, I'll start listening.
I'm not wedded to high immigration so if you can make it economically easier for British people to have and support larger families, then great. Realistically though, that isn't going to come from a right wing party.
What I'm not prepared to do is pay significantly higher taxes (rising year on year) to help support an aging population purely because some people don't want there to be "too many" foreigners.
I'm also not buying that immigration is the primary factor straining our infrastructure. Even with high immigration, our population growth is very modest (it'd be shrinking year on year without it). It screams lack of investment.