Why can't we simply configure clients to use a phonebook we like, rather than the phonebook we don't like?

Today, it's relatively easy to create something like a piece of software and a db of alternative roots. And any clients which have that kit installed are suddenly simply ignoring pieces of what the traditional roots say.

Yes it would be fractured for a while. But it's no worse than say, dns over https, and the way say, you can't reach archive.is while your browser is using doh, but can when you turn doh off. (unless they finally fixed that, but that was the situation for a ridiculously long time after both cloudflare and archive.is were made aware.)

We already have such things today, so might as well employ it as well as suffer it.