That’s a shame, it would be good to gain a fuller understanding. I wonder if it’s based on a given investment trust’s KID. BSIF’s, for example, does say:
The Fund is not primarily targeted at retail investors. The Shares are intended for sophisticated investors and private clients who understand and are willing to assume the risk of capital loss and understand that there may be limited buyers for the underlying investments of the Fund and who have sufficient resources to be able to bear losses (which may equal the whole amount invested).
NESF’s doesn’t seem as clear cut which may be why that’s still available. NBMI’s KID says something similar to BSIF’s and that was part of the cull too.
Edit: I think this may be it, there definitely appears to be a pattern. IHR’s KID says it’s only for ‘professionally advised or knowledgeable retail investors’ as do the KIDs for VOF and APAX.