"In December 2011, Cummings married Mary Wakefield, who became the deputy editor of The Spectator"
Add in Andrew Gilligan, formerly of the Sunday Times and author of some very good GC articles, who is another No 10 advisor, and we can be fairly confident than this PM will not be promoting self-ID.
However...
Cummings led the Vote Leave campaign. In the same way as GC women are angry at not being listened to by the establishment, including the Civil Service, the BBC and major charities, and being called transphobes for questioning a PC status quo, I suspect Brexiteers are frustrated by the abuse they received and the lack of support from Remainers within the Civil Service.
This is a far stronger Conservative Government than we have seen since the days of Thatcher, not only because of the size of the majority, but because it is not longer divided by Europe. It also has the weakest opposition in history, not only in Parliament, but also because a decade of wokeness means that media outlets such as the Guardian no longer have the capacity for reasoned critical argument. Tories are evil type Twitter arguments won't cut it with a Government who will be determinedly one-nation and wanting to keep their new voters so delivering some popular policies along with some serious "reforms". Not least many FWR posters would welcome a halting of the regulatory creep towards self-ID. (I want an invitation to a Serwotka family dinner and a discussion on the pros and cons of a Boris PM.)
However Boris, and Cummings, are not universally liked within the Conservative party so we can expect to see critical analysis from the Tory media.
Here is an example.
www.dailymail.co.uk/wires/pa/article-7845363/Union-bosses-hit-PM-ally-warns-civil-service-set-seismic-change.html