Well now we get into subjectivity. Yes, if immigration stopped tomorrow those issues wouldn't disappear over night. But they also wouldn't continue to get worse, in their opinions.
One thing that I do agree with the Reform lot on, is the structure of the economics of immigration. Immigration is almost always a net economic benefit for a nation but there's a lot of caveats to that. The biggest caveat being this - immigration is a stealth tax on the working classes that benefit the generally middle classes. It keeps unskilled labour costs depressed through simple supply and demand as well as increasing competition for council housing, GPs appointments and all the rest you mention. That's sort of inarguable those last few things, that's just a function of having more people here no matter where they come from.
These factors are generally not an issue though to the middle to high income earners, especially business owners. They get cheap labour to keep costs down. To low incomes though, having more people in competition, especially if those people are classed as in desperate situations for asylum meaning they'll move to the front of any queue, it has devastating effects.And the fact that many have travelled through numerous safe countries only to get here and then jump the queue sticks in their craw, rightfully imo. I'm in Labour heartland and Reform came 2nd here. Any visit to a local pub in the area will tell you exactly what people are concerned about.
Immigration is a net economic benefit but it's paid for by the lowest earners, and in the last few decades without their consent.
The rise of the so called Metropolitan left winger has really hurt the lefts view on this issue. Before New Labour, they were often anti-immigration. Trade unionists understood that introducing more immigrants to the workforce would do nothing but help businesses have more power and not have the culture education of the importance of trade unionists and collectivism.
The "anti immigration is racist" argument was dreamt up by Mandelson and his ilk as one tactic of browbeating socialists in line. "Oh, the NF don't like immigration either, youre not secretly a RACIST are you??" Etc. It worked incredibly to the point now that a ton of people seem to believe that any political opinion that doesn't advocate open borders is therefore secret and hidden racism.
You see if you don't want more immigration and you're pissed off about it then you vote for Reform. And if you vote Reform then you're secretly a racist. And if you're a racist then you're secretly a fascist. And if you're a fascist then you're secretly a Nazi. And it's ok to denigrate, bully, harass, assault and kill Nazis because they're bad.
Watching this shit happen in real time is frustrating.
This.