The scheme ended, thankfully, and so cannot trap other people who are not fully aware of the details.
My take is that it encouraged people to buy over-priced, often low quality, new builds - especially flats - creating a debt trap. The value of the sub-standard home is much less than the price paid and can therefore prevent people from moving on.
From the article above,
"But many homebuyers have accused private developers of using the scheme to inflate the price of new flats, effectively pocketing the state subsidy for themselves.
A report in January last year by the Lords’ built environment committee found the loans inflated prices by more than their subsidy value in areas where it was needed the most, concluding that “this funding would be better spent on increasing housing supply” directly, through local authority and housing association building projects. "