We discussed removing public client support for part 2 in: https://bitbucket.org/openid/fapi/issues/158/fapi-part-2-request-object-for-public
I think we should consider removing it in part 1 as well. At the very least this clause will need to be removed or updated as its not that clear:
- shall support [RFC7636] or the mechanisms defined in Financial-grade API - Part 2;
In addition I suggest that we have a clause recommending the dynamic registration of confidential clients for the "mobile app" use case.