The benefits system may well recognise the fact of a spectrum of ability to work - in fact it's in their advantage to, in terms of claim reduction. What they don't do is meaningfully acknowledge that fact legislatively or in any way that assists people on that spectrum to work. We've seen lip service via "disability advisors" in JC+ (most of which positions are currently being withdrawn), but nothing that feeds into employment legislation.
Knocking people off of a benefit without assisting them to find alternative income sources consonant with their medical issues, is morally reprehensible, and yet this is exactly what's happening, and exactly what is contributing to suicides and self-harm.