We could argue about the overton window or whatever but far-right seems descriptive given that he is to the right of our traditional centre-right party, the tories. The Reform manifesto was proposing completely dismantling the benefits system for example, which would be a “far-right” policy imo.
I agree with your other comments that he’s not a fascist though. Fascism is a really specifc political doctorine that basically claims that the needs of the state trump any specific individual’s needs. People online tend to use it like a blanket term to describe any opinion that they don’t like which is to the right of their own (ditto with “nazi”). The BNP were literally fascist, and there is a real difference between their position and the Reform one.