anyone who questions or criticizes immigration is just racist

If they start making valid arguments instead of just "get rid of immigrants" then I might listen. Like we could talk about different visas, I generally think the skilled worker visa is alright and something to encourage. Extending or restricting some industries might be a point to consider in some cases too.

But when the people I see smashing up the street and leaving nails or broken glass in front of my house just complain about anyone brown, I won't take them seriously.

The solution to this problem is not to end immigration but to: ensure that the minimum wage is more than a poverty wage; ensure that migrant workers join unions where available; ensure that migrant workers have the same rights as non-migrant workers and are not afraid of being brutalised by immigration police and being sent home if they lose their job; ensure that undocumented migrants are given a route to become legal and documented citizens to undermine modern day slavery and cash-in-hand tax avoiding bosses.

Demonising migrants and empowering the state to deport them en masse and brutalise them just causes more wage suppression as immigrant workers never fight against their bosses alongside non-migrant workers and accept worse pay and working conditions in order to keep their job and immigration status.