Her statement was actually pretty good - it identified the main issues and named the frustration of people wanting to feel the effects of policy themselves. Competence is fine but without tangible evidence for normal working people it's always going to lose against rhetoric and slogans with simple fixes to complex problems.
If you want immigration to come down, take a look at the graph. Which direction do you see the numbers going?
And benefits - yes, pensions are a huge cost to the state, but the triple-lock is a political grenade so no party wants to touch it.
The biggest problems are around literacy and communication of this stuff. The average person is clueless as to the actual numbers, and the average politician is hopeless at communicating them effectively.
If immigration numbers are falling, that tells one story.
If small towns are quickly receiving large numbers of non-EU migrants, who are unskilled, unsupported, and culturally incompatible with their neighbours, that's a separate story. And it's one that drives a lot of people's voting intention, whether it's first-hand, or third-hand, or based on misinformation from a party with a slicker social media operation and no squeamishness about outright lying to get votes.
So yes - welfare should be discussed. Immigration should be discussed. But it's pointless if people don't 1) use tangible, evidence-based points and 2) listen to the other side and talk to each other like human beings.