You may as well argue it was cowardice on the part of the major parties not to stand. It wasn't; it was sensible, as was Farage's decision to stay away.
That speech is bullshit. The Tories have no intention of dealing with the problem, they spent fourteen years proving that. I do find your faith in them rather baffling.
In response to your first point, the main parties were, as you say, sensible to have nothing to do with this farrago – but it was hardly appropriate for Farage to stay away from something he had himself set in motion. ("Oh, was there a car-crash? Nothing to do with me, guv.")
With regard to your second point. I have no illusions about the various Conservative governments of 2010 to 2024. Each was worse than the previous one, except in the case of Rishi Sunak, who did his best to steady the ship.
Kemi Badenoch shows promise. I would put it no stronger than that. And I think that the Conservatives do “have an intention” to deal with the problem of excessive and / or illegal immigration but – if they ever get into the government again (doesn’t look very likely at the moment!) – they would be constrained by many difficult realities. Just as Reform UK would be (also unlikely to form a government in the foreseeable future, thank God).
The sad truth is that the policies, bad decisions and unavoidable realities of the past 75 years have made Britain much more “diverse” than is good for it – not least because the numbers involved mean that proper assimilation has often been impossible and / or that some communities anyway prefer to keep to themselves, speaking their own languages and sticking to their own traditions.
What’s the answer? To gather together all the tinted people and ship them off to concentration camps? The late Herr Hitler did something similar in the 1930s and 1940s, and the verdict of history has been largely negative.
Within the lifetimes of the younger members of this site, the majority of the English population will be of “minority” origin. And there’s not a thing anyone can do about it.
And that’s before we take into account the imminent mass movement northwards of people from north and sub-Saharan Africa.